diff --git a/src/TinyGsmClientA6.h b/src/TinyGsmClientA6.h
index da2b027..5efd20d 100644
--- a/src/TinyGsmClientA6.h
+++ b/src/TinyGsmClientA6.h
@@ -39,11 +39,27 @@ enum RegStatus {
 };
 
 
+//============================================================================//
+//============================================================================//
+//                       Declaration of the TinyGsmA6 Class
+//============================================================================//
+//============================================================================//
+
+
+
 class TinyGsmA6
 {
 
 public:
 
+
+//============================================================================//
+//============================================================================//
+//                          The A6 Client Class
+//============================================================================//
+//============================================================================//
+
+
 class GsmClient : public Client
 {
   friend class TinyGsmA6;
@@ -167,9 +183,28 @@ private:
   RxFifo        rx;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The A6 Does not have a secure client!
+//============================================================================//
+//============================================================================//
+
+
+
+//============================================================================//
+//============================================================================//
+//                          The A6 Modem Functions
+//============================================================================//
+//============================================================================//
+
+
 public:
 
+#ifdef GSM_DEFAULT_STREAM
+  TinyGsmA6(Stream& stream = GSM_DEFAULT_STREAM)
+#else
   TinyGsmA6(Stream& stream)
+#endif
     : stream(stream)
   {
     memset(sockets, 0, sizeof(sockets));
@@ -241,6 +276,8 @@ public:
     return res;
   }
 
+  bool hasSSL() { return false; }
+
   /*
    * Power functions
    */
@@ -313,17 +350,6 @@ public:
     return SIM_ERROR;
   }
 
-  RegStatus getRegistrationStatus() {
-    sendAT(GF("+CREG?"));
-    if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
-      return REG_UNKNOWN;
-    }
-    streamSkipUntil(','); // Skip format (0)
-    int status = stream.readStringUntil('\n').toInt();
-    waitResponse();
-    return (RegStatus)status;
-  }
-
   String getOperator() {
     sendAT(GF("+COPS=3,0")); // Set format
     waitResponse();
@@ -342,6 +368,17 @@ public:
    * Generic network functions
    */
 
+   RegStatus getRegistrationStatus() {
+     sendAT(GF("+CREG?"));
+     if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
+       return REG_UNKNOWN;
+     }
+     streamSkipUntil(','); // Skip format (0)
+     int status = stream.readStringUntil('\n').toInt();
+     waitResponse();
+     return (RegStatus)status;
+   }
+
   int getSignalQuality() {
     sendAT(GF("+CSQ"));
     if (waitResponse(GF(GSM_NL "+CSQ:")) != 1) {
@@ -367,6 +404,26 @@ public:
     return false;
   }
 
+  String getLocalIP() {
+    sendAT(GF("+CIFSR"));
+    String res;
+    if (waitResponse(10000L, res) != 1) {
+      return "";
+    }
+    res.replace(GSM_NL "OK" GSM_NL, "");
+    res.replace(GSM_NL, "");
+    res.trim();
+    return res;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
+  /*
+   * WiFi functions
+   */
+
   /*
    * GPRS functions
    */
@@ -423,22 +480,6 @@ public:
     return (res == 1);
   }
 
-  String getLocalIP() {
-    sendAT(GF("+CIFSR"));
-    String res;
-    if (waitResponse(10000L, res) != 1) {
-      return "";
-    }
-    res.replace(GSM_NL "OK" GSM_NL, "");
-    res.replace(GSM_NL, "");
-    res.trim();
-    return res;
-  }
-
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
-  }
-
   /*
    * Messaging functions
    */
diff --git a/src/TinyGsmClientESP8266.h b/src/TinyGsmClientESP8266.h
index 8dec021..805a6d6 100644
--- a/src/TinyGsmClientESP8266.h
+++ b/src/TinyGsmClientESP8266.h
@@ -9,7 +9,7 @@
 #ifndef TinyGsmClientESP8266_h
 #define TinyGsmClientESP8266_h
 
-//#define TINY_GSM_DEBUG Serial
+// #define TINY_GSM_DEBUG Serial
 
 #if !defined(TINY_GSM_RX_BUFFER)
   #define TINY_GSM_RX_BUFFER 512
@@ -24,18 +24,36 @@ static const char GSM_OK[] TINY_GSM_PROGMEM = "OK" GSM_NL;
 static const char GSM_ERROR[] TINY_GSM_PROGMEM = "ERROR" GSM_NL;
 static unsigned TINY_GSM_TCP_KEEP_ALIVE = 120;
 
+// <stat> status of ESP8266 station interface
+// 2 : ESP8266 station connected to an AP and has obtained IP
+// 3 : ESP8266 station created a TCP or UDP transmission
+// 4 : the TCP or UDP transmission of ESP8266 station disconnected
+// 5 : ESP8266 station did NOT connect to an AP
 enum RegStatus {
-  REG_UNREGISTERED = 0,
-  REG_SEARCHING    = 2,
-  REG_DENIED       = 3,
-  REG_OK_HOME      = 1,
-  REG_OK_ROAMING   = 5,
-  REG_UNKNOWN      = 4,
+  REG_OK_IP        = 2,
+  REG_OK_TCP       = 3,
+  REG_UNREGISTERED = 4,
+  REG_DENIED       = 5,
+  REG_UNKNOWN      = 6,
 };
 
+
+//============================================================================//
+//============================================================================//
+//                     Declaration of the TinyGsmESP8266 Class
+//============================================================================//
+//============================================================================//
+
+
 class TinyGsmESP8266
 {
 
+  //============================================================================//
+  //============================================================================//
+  //                          The ESP8266 Client Class
+  //============================================================================//
+  //============================================================================//
+
 public:
 
 class GsmClient : public Client
@@ -158,6 +176,13 @@ private:
   RxFifo        rx;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The Secure ESP8266 Client Class
+//============================================================================//
+//============================================================================//
+
+
 class GsmClientSecure : public GsmClient
 {
 public:
@@ -176,9 +201,20 @@ public:
   }
 };
 
+
+//============================================================================//
+//============================================================================//
+//                          The ESP8266 Modem Functions
+//============================================================================//
+//============================================================================//
+
 public:
 
+#ifdef GSM_DEFAULT_STREAM
+  TinyGsmESP8266(Stream& stream = GSM_DEFAULT_STREAM)
+#else
   TinyGsmESP8266(Stream& stream)
+#endif
     : stream(stream)
   {
     memset(sockets, 0, sizeof(sockets));
@@ -239,29 +275,7 @@ public:
     return res;
   }
 
-  bool hasSSL() {
-    return true;
-  }
-
-  RegStatus getRegistrationStatus() {
-    sendAT(GF("+CIPSTATUS"));
-    int res1 = waitResponse(3000, GF("STATUS:"));
-    int res2 = 0;
-    if (res1 == 1) {
-      res2 = waitResponse(GFP(GSM_ERROR), GF("2"), GF("3"), GF("4"), GF("5"));
-    }
-    // <stat> status of ESP8266 station interface
-    // 2 : ESP8266 station connected to an AP and has obtained IP
-    // 3 : ESP8266 station created a TCP or UDP transmission
-    // 4 : the TCP or UDP transmission of ESP8266 station disconnected
-    // 5 : ESP8266 station did NOT connect to an AP
-    waitResponse();  // Returns an OK after the status
-    if (res2 == 2) return REG_OK_HOME;
-    if (res2 == 3) return REG_OK_HOME;
-    if (res2 == 4) return REG_UNREGISTERED;
-    if (res2 == 5) return REG_DENIED;
-    else return REG_UNKNOWN;
-  }
+  bool hasSSL() { return true; }
 
   /*
    * Power functions
@@ -282,11 +296,30 @@ public:
     return init();
   }
 
+  bool poweroff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool radioOff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool sleepEnable(bool enable = true) TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+
+  /*
+   * SIM card functions
+   */
+
 
   /*
    * Generic network functions
    */
 
+   RegStatus getRegistrationStatus() {
+     sendAT(GF("+CIPSTATUS"));
+    if (waitResponse(3000, GF("STATUS:")) != 1) return REG_UNKNOWN;
+    int status = waitResponse(GFP(GSM_ERROR), GF("2"), GF("3"), GF("4"), GF("5"));
+     waitResponse();  // Returns an OK after the status
+    return (RegStatus)status;
+   }
+
   int getSignalQuality() {
     sendAT(GF("+CWJAP_CUR?"));
     int res1 = waitResponse(GF("No AP"), GF("+CWJAP_CUR:"));
@@ -304,7 +337,7 @@ public:
 
   bool isNetworkConnected()  {
     RegStatus s = getRegistrationStatus();
-    return (s == REG_OK_HOME || s == REG_OK_ROAMING);
+    return (s == REG_OK_IP || s == REG_OK_TCP);
   }
 
   bool waitForNetwork(unsigned long timeout = 60000L) {
@@ -323,6 +356,21 @@ public:
     return false;
   }
 
+  String getLocalIP() {
+    sendAT(GF("+CIPSTA_CUR??"));
+    int res1 = waitResponse(GF("ERROR"), GF("+CWJAP_CUR:"));
+    if (res1 != 2) {
+      return "";
+    }
+    String res2 = stream.readStringUntil('"');
+    waitResponse();
+    return res2;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
   /*
    * WiFi functions
    */
@@ -353,20 +401,27 @@ public:
     return retVal;
   }
 
-  String getLocalIP() {
-    sendAT(GF("+CIPSTA_CUR??"));
-    int res1 = waitResponse(GF("ERROR"), GF("+CWJAP_CUR:"));
-    if (res1 != 2) {
-      return "";
-    }
-    String res2 = stream.readStringUntil('"');
-    waitResponse();
-    return res2;
-  }
+  /*
+   * GPRS functions
+   */
 
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
-  }
+  /*
+   * Messaging functions
+   */
+
+  /*
+   * Location functions
+   */
+
+  String getGsmLocation() TINY_GSM_ATTR_NOT_AVAILABLE;
+
+  /*
+   * Battery functions
+   */
+
+  uint16_t getBattVoltage() TINY_GSM_ATTR_NOT_AVAILABLE;
+
+  int getBattPercent() TINY_GSM_ATTR_NOT_AVAILABLE;
 
 protected:
 
@@ -400,7 +455,7 @@ protected:
 
   bool modemGetConnected(uint8_t mux) {
     RegStatus s = getRegistrationStatus();
-    return (s == REG_OK_HOME || s == REG_OK_ROAMING);
+    return (s == REG_OK_IP || s == REG_OK_TCP);
   }
 
 public:
@@ -436,7 +491,7 @@ public:
     streamWrite("AT", cmd..., GSM_NL);
     stream.flush();
     TINY_GSM_YIELD();
-    //DBG("### AT:", cmd...);
+    // DBG("### AT:", cmd...);
   }
 
   // TODO: Optimize this!
diff --git a/src/TinyGsmClientM590.h b/src/TinyGsmClientM590.h
index e0d9431..7bc276c 100644
--- a/src/TinyGsmClientM590.h
+++ b/src/TinyGsmClientM590.h
@@ -9,7 +9,7 @@
 #ifndef TinyGsmClientM590_h
 #define TinyGsmClientM590_h
 
-//#define TINY_GSM_DEBUG Serial
+// #define TINY_GSM_DEBUG Serial
 
 #if !defined(TINY_GSM_RX_BUFFER)
   #define TINY_GSM_RX_BUFFER 256
@@ -39,9 +39,21 @@ enum RegStatus {
 };
 
 
+//============================================================================//
+//============================================================================//
+//                    Declaration of the TinyGsmM590 Class
+//============================================================================//
+//============================================================================//
+
 class TinyGsmM590
 {
 
+//============================================================================//
+//============================================================================//
+//                          The M590 Client Class
+//============================================================================//
+//============================================================================//
+
 public:
 
 class GsmClient : public Client
@@ -158,15 +170,33 @@ public:
   String remoteIP() TINY_GSM_ATTR_NOT_IMPLEMENTED;
 
 private:
-  TinyGsmM590*      at;
+  TinyGsmM590*  at;
   uint8_t       mux;
   bool          sock_connected;
   RxFifo        rx;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The M590 Has no Secure client!
+//============================================================================//
+//============================================================================//
+
+
+
+//============================================================================//
+//============================================================================//
+//                          The M590 Modem Functions
+//============================================================================//
+//============================================================================//
+
 public:
 
+#ifdef GSM_DEFAULT_STREAM
+  TinyGsmM590(Stream& stream = GSM_DEFAULT_STREAM)
+#else
   TinyGsmM590(Stream& stream)
+#endif
     : stream(stream)
   {
     memset(sockets, 0, sizeof(sockets));
@@ -243,6 +273,8 @@ public:
     return res;
   }
 
+  bool hasSSL() { return false; }
+
   /*
    * Power functions
    */
@@ -322,17 +354,6 @@ public:
     return SIM_ERROR;
   }
 
-  RegStatus getRegistrationStatus() {
-    sendAT(GF("+CREG?"));
-    if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
-      return REG_UNKNOWN;
-    }
-    streamSkipUntil(','); // Skip format (0)
-    int status = stream.readStringUntil('\n').toInt();
-    waitResponse();
-    return (RegStatus)status;
-  }
-
   String getOperator() {
     sendAT(GF("+COPS?"));
     if (waitResponse(GF(GSM_NL "+COPS:")) != 1) {
@@ -348,6 +369,17 @@ public:
    * Generic network functions
    */
 
+   RegStatus getRegistrationStatus() {
+     sendAT(GF("+CREG?"));
+     if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
+       return REG_UNKNOWN;
+     }
+     streamSkipUntil(','); // Skip format (0)
+     int status = stream.readStringUntil('\n').toInt();
+     waitResponse();
+     return (RegStatus)status;
+   }
+
   int getSignalQuality() {
     sendAT(GF("+CSQ"));
     if (waitResponse(GF(GSM_NL "+CSQ:")) != 1) {
@@ -373,10 +405,30 @@ public:
     return false;
   }
 
+  String getLocalIP() {
+    sendAT(GF("+XIIC?"));
+    if (waitResponse(GF(GSM_NL "+XIIC:")) != 1) {
+      return "";
+    }
+    stream.readStringUntil(',');
+    String res = stream.readStringUntil('\n');
+    waitResponse();
+    res.trim();
+    return res;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
+  /*
+   * WiFi functions
+   */
+
   /*
    * GPRS functions
    */
-  bool gprsConnect(const char* apn, const char* user, const char* pwd) {
+  bool gprsConnect(const char* apn, const char* user = "", const char* pwd = "") {
     gprsDisconnect();
 
     sendAT(GF("+XISP=0"));
@@ -429,22 +481,6 @@ public:
     return res == 1;
   }
 
-  String getLocalIP() {
-    sendAT(GF("+XIIC?"));
-    if (waitResponse(GF(GSM_NL "+XIIC:")) != 1) {
-      return "";
-    }
-    stream.readStringUntil(',');
-    String res = stream.readStringUntil('\n');
-    waitResponse();
-    res.trim();
-    return res;
-  }
-
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
-  }
-
   /*
    * Messaging functions
    */
@@ -596,7 +632,7 @@ public:
     streamWrite("AT", cmd..., GSM_NL);
     stream.flush();
     TINY_GSM_YIELD();
-    //DBG("### AT:", cmd...);
+    // DBG("### AT:", cmd...);
   }
 
   // TODO: Optimize this!
diff --git a/src/TinyGsmClientSIM800.h b/src/TinyGsmClientSIM800.h
index acdfcf8..056adc7 100644
--- a/src/TinyGsmClientSIM800.h
+++ b/src/TinyGsmClientSIM800.h
@@ -9,8 +9,8 @@
 #ifndef TinyGsmClientSIM800_h
 #define TinyGsmClientSIM800_h
 
-//#define TINY_GSM_DEBUG Serial
-//#define TINY_GSM_USE_HEX
+// #define TINY_GSM_DEBUG Serial
+// #define TINY_GSM_USE_HEX
 
 #if !defined(TINY_GSM_RX_BUFFER)
   #define TINY_GSM_RX_BUFFER 64
@@ -40,9 +40,22 @@ enum RegStatus {
 };
 
 
+//============================================================================//
+//============================================================================//
+//                    Declaration of the TinyGsmSim800 Class
+//============================================================================//
+//============================================================================//
+
 class TinyGsmSim800
 {
 
+//============================================================================//
+//============================================================================//
+//                          The Sim800 Client Class
+//============================================================================//
+//============================================================================//
+
+
 public:
 
 class GsmClient : public Client
@@ -180,6 +193,13 @@ private:
   RxFifo        rx;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The SIM800 Secure Client
+//============================================================================//
+//============================================================================//
+
+
 class GsmClientSecure : public GsmClient
 {
 public:
@@ -198,9 +218,19 @@ public:
   }
 };
 
+//============================================================================//
+//============================================================================//
+//                          The SIM800 Modem Functions
+//============================================================================//
+//============================================================================//
+
 public:
 
+#ifdef GSM_DEFAULT_STREAM
+  TinyGsmSim800(Stream& stream = GSM_DEFAULT_STREAM)
+#else
   TinyGsmSim800(Stream& stream)
+#endif
     : stream(stream)
   {
     memset(sockets, 0, sizeof(sockets));
@@ -391,17 +421,6 @@ public:
     return SIM_ERROR;
   }
 
-  RegStatus getRegistrationStatus() {
-    sendAT(GF("+CREG?"));
-    if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
-      return REG_UNKNOWN;
-    }
-    streamSkipUntil(','); // Skip format (0)
-    int status = stream.readStringUntil('\n').toInt();
-    waitResponse();
-    return (RegStatus)status;
-  }
-
   String getOperator() {
     sendAT(GF("+COPS?"));
     if (waitResponse(GF(GSM_NL "+COPS:")) != 1) {
@@ -417,6 +436,17 @@ public:
    * Generic network functions
    */
 
+   RegStatus getRegistrationStatus() {
+     sendAT(GF("+CREG?"));
+     if (waitResponse(GF(GSM_NL "+CREG:")) != 1) {
+       return REG_UNKNOWN;
+     }
+     streamSkipUntil(','); // Skip format (0)
+     int status = stream.readStringUntil('\n').toInt();
+     waitResponse();
+     return (RegStatus)status;
+   }
+
   int getSignalQuality() {
     sendAT(GF("+CSQ"));
     if (waitResponse(GF(GSM_NL "+CSQ:")) != 1) {
@@ -442,10 +472,30 @@ public:
     return false;
   }
 
+  String getLocalIP() {
+    sendAT(GF("+CIFSR;E0"));
+    String res;
+    if (waitResponse(10000L, res) != 1) {
+      return "";
+    }
+    res.replace(GSM_NL "OK" GSM_NL, "");
+    res.replace(GSM_NL, "");
+    res.trim();
+    return res;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
+  /*
+   * WiFi functions
+   */
+
   /*
    * GPRS functions
    */
-  bool gprsConnect(const char* apn, const char* user, const char* pwd) {
+  bool gprsConnect(const char* apn, const char* user = "", const char* pwd = "") {
     gprsDisconnect();
 
     // Set the Bearer for the IP
@@ -561,22 +611,6 @@ public:
     return true;
   }
 
-  String getLocalIP() {
-    sendAT(GF("+CIFSR;E0"));
-    String res;
-    if (waitResponse(10000L, res) != 1) {
-      return "";
-    }
-    res.replace(GSM_NL "OK" GSM_NL, "");
-    res.replace(GSM_NL, "");
-    res.trim();
-    return res;
-  }
-
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
-  }
-
   /*
    * Messaging functions
    */
@@ -668,6 +702,7 @@ public:
   /*
    * Battery functions
    */
+
   // Use: float vBatt = modem.getBattVoltage() / 1000.0;
   uint16_t getBattVoltage() {
     sendAT(GF("+CBC"));
@@ -812,7 +847,7 @@ public:
     streamWrite("AT", cmd..., GSM_NL);
     stream.flush();
     TINY_GSM_YIELD();
-    //DBG("### AT:", cmd...);
+    // DBG("### AT:", cmd...);
   }
 
   // TODO: Optimize this!
diff --git a/src/TinyGsmClientSIM808.h b/src/TinyGsmClientSIM808.h
index 2b9c49a..b49ab85 100644
--- a/src/TinyGsmClientSIM808.h
+++ b/src/TinyGsmClientSIM808.h
@@ -11,6 +11,13 @@
 
 #include <TinyGsmClientSIM800.h>
 
+
+//============================================================================//
+//============================================================================//
+//              Declaration and Definitio of the TinyGsmSim808 Class
+//============================================================================//
+//============================================================================//
+
 class TinyGsmSim808: public TinyGsmSim800
 {
 
diff --git a/src/TinyGsmClientU201.h b/src/TinyGsmClientU201.h
index 64d6f2a..f5b2a35 100644
--- a/src/TinyGsmClientU201.h
+++ b/src/TinyGsmClientU201.h
@@ -9,7 +9,7 @@
 #ifndef TinyGsmClientU201_h
 #define TinyGsmClientU201_h
 
-//#define TINY_GSM_DEBUG Serial
+// #define TINY_GSM_DEBUG Serial
 
 #if !defined(TINY_GSM_RX_BUFFER)
   #define TINY_GSM_RX_BUFFER 64
@@ -39,9 +39,22 @@ enum RegStatus {
 };
 
 
+//============================================================================//
+//============================================================================//
+//                   Declaration of the TinyGsmU201 Class
+//============================================================================//
+//============================================================================//
+
 class TinyGsmU201
 {
 
+//============================================================================//
+//============================================================================//
+//                          The U201 Client Class
+//============================================================================//
+//============================================================================//
+
+
 public:
 
 class GsmClient : public Client
@@ -169,6 +182,13 @@ private:
   RxFifo        rx;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The Secure U201 Client Class
+//============================================================================//
+//============================================================================//
+
+
 class GsmClientSecure : public GsmClient
 {
 public:
@@ -188,6 +208,13 @@ public:
   }
 };
 
+
+//============================================================================//
+//============================================================================//
+//                          The U201 Modem Functions
+//============================================================================//
+//============================================================================//
+
 public:
 
 #ifdef GSM_DEFAULT_STREAM
@@ -258,6 +285,10 @@ public:
     return waitResponse() == 1;
   }
 
+  String getModemInfo() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool hasSSL() { return true; }
+
   /*
    * Power functions
    */
@@ -276,6 +307,10 @@ public:
 
   bool poweroff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
 
+  bool radioOff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool sleepEnable(bool enable = true) TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
   /*
    * SIM card functions
    */
@@ -326,17 +361,6 @@ public:
     return SIM_ERROR;
   }
 
-  RegStatus getRegistrationStatus() {
-    sendAT(GF("+CGREG?"));
-    if (waitResponse(GF(GSM_NL "+CGREG:")) != 1) {
-      return REG_UNKNOWN;
-    }
-    streamSkipUntil(','); // Skip format (0)
-    int status = stream.readStringUntil('\n').toInt();
-    waitResponse();
-    return (RegStatus)status;
-  }
-
   String getOperator() {
     sendAT(GF("+COPS?"));
     if (waitResponse(GF(GSM_NL "+COPS:")) != 1) {
@@ -352,6 +376,17 @@ public:
    * Generic network functions
    */
 
+   RegStatus getRegistrationStatus() {
+     sendAT(GF("+CGREG?"));
+     if (waitResponse(GF(GSM_NL "+CGREG:")) != 1) {
+       return REG_UNKNOWN;
+     }
+     streamSkipUntil(','); // Skip format (0)
+     int status = stream.readStringUntil('\n').toInt();
+     waitResponse();
+     return (RegStatus)status;
+   }
+
   int getSignalQuality() {
     sendAT(GF("+CSQ"));
     if (waitResponse(GF(GSM_NL "+CSQ:")) != 1) {
@@ -377,10 +412,28 @@ public:
     return false;
   }
 
+  String getLocalIP() {
+    sendAT(GF("+CIFSR;E0"));
+    String res;
+    if (waitResponse(10000L, res) != 1) {
+      return "";
+    }
+    res.trim();
+    return res;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
+  /*
+   * WiFi functions
+   */
+
   /*
    * GPRS functions
    */
-  bool gprsConnect(const char* apn, const char* user, const char* pwd) {
+  bool gprsConnect(const char* apn, const char* user = "", const char* pwd = "") {
     gprsDisconnect();
 
     sendAT(GF("+CGATT=1"));
@@ -441,19 +494,6 @@ public:
     return true;
   }
 
-  String getLocalIP() {
-    sendAT(GF("+CIFSR;E0"));
-    String res;
-    if (waitResponse(10000L, res) != 1) {
-      return "";
-    }
-    res.trim();
-    return res;
-  }
-
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
-  }
   /*
    * Messaging functions
    */
@@ -483,6 +523,7 @@ public:
   /*
    * Battery functions
    */
+
   // Use: float vBatt = modem.getBattVoltage() / 1000.0;
   uint16_t getBattVoltage() {
     sendAT(GF("+CIND"));
@@ -611,7 +652,7 @@ public:
     streamWrite("AT", cmd..., GSM_NL);
     stream.flush();
     TINY_GSM_YIELD();
-    //DBG("### AT:", cmd...);
+    // DBG("### AT:", cmd...);
   }
 
   // TODO: Optimize this!
@@ -632,7 +673,7 @@ public:
       TINY_GSM_YIELD();
       while (stream.available() > 0) {
         int a = stream.read();
-        if (a < 0) continue;
+        if (a <= 0) continue; // Skip 0x00 bytes, just in case
         data += (char)a;
         if (r1 && data.endsWith(r1)) {
           index = 1;
diff --git a/src/TinyGsmClientXBee.h b/src/TinyGsmClientXBee.h
index 60be866..c1c8ff9 100644
--- a/src/TinyGsmClientXBee.h
+++ b/src/TinyGsmClientXBee.h
@@ -11,9 +11,6 @@
 
 // #define TINY_GSM_DEBUG Serial
 
-#if !defined(TINY_GSM_RX_BUFFER)
-  #define TINY_GSM_RX_BUFFER 64
-#endif
 
 #define TINY_GSM_MUX_COUNT 1  // Multi-plexing isn't supported using command mode
 
@@ -29,24 +26,36 @@ enum SimStatus {
   SIM_LOCKED = 2,
 };
 
-enum XBeeType {
-  XBEE_CELL  = 0,
-  XBEE_WIFI  = 1,
-};
-
 enum RegStatus {
   REG_UNREGISTERED = 0,
   REG_SEARCHING    = 2,
   REG_DENIED       = 3,
-  REG_OK_HOME      = 1,
-  REG_OK_ROAMING   = 5,
+  REG_OK           = 1,
   REG_UNKNOWN      = 4,
 };
 
+enum XBeeType {
+  XBEE_CELL  = 0,
+  XBEE_WIFI  = 1,
+};
+
+
+//============================================================================//
+//============================================================================//
+//                   Declaration of the TinyGsmXBee Class
+//============================================================================//
+//============================================================================//
 
 class TinyGsmXBee
 {
 
+//============================================================================//
+//============================================================================//
+//                          The XBee Client Class
+//============================================================================//
+//============================================================================//
+
+
 public:
 
 class GsmClient : public Client
@@ -116,7 +125,6 @@ public:
 
   virtual size_t write(const uint8_t *buf, size_t size) {
     TINY_GSM_YIELD();
-    //at->maintain();
     return at->modemSend(buf, size, mux);
   }
 
@@ -162,6 +170,13 @@ private:
   bool          sock_connected;
 };
 
+//============================================================================//
+//============================================================================//
+//                          The Secure XBee Client Class
+//============================================================================//
+//============================================================================//
+
+
 class GsmClientSecure : public GsmClient
 {
 public:
@@ -197,6 +212,13 @@ public:
   }
 };
 
+
+//============================================================================//
+//============================================================================//
+//                          The XBee Modem Functions
+//============================================================================//
+//============================================================================//
+
 public:
 
 #ifdef GSM_DEFAULT_STREAM
@@ -205,9 +227,7 @@ public:
   TinyGsmXBee(Stream& stream)
 #endif
     : stream(stream)
-  {
-    memset(sockets, 0, sizeof(sockets));
-  }
+  {}
 
   /*
    * Basic functions
@@ -290,6 +310,17 @@ public:
     return ret_val;
   }
 
+  String getModemInfo() {
+    String modemInf = "";
+    if (!commandMode()) return modemInf;  // Try up to 10 times for the init
+
+    sendAT(GF("HS"));  // Get the "Hardware Series"
+    modemInf += readResponse();
+
+    exitCommand();
+    return modemInf;
+  }
+
   bool hasSSL() {
     if (beeType == XBEE_WIFI) return false;
     else return true;
@@ -349,6 +380,12 @@ public:
     exitCommand();
   }
 
+  bool poweroff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool radioOff() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
+  bool sleepEnable() TINY_GSM_ATTR_NOT_IMPLEMENTED;
+
   /*
    * SIM card functions
    */
@@ -377,65 +414,83 @@ public:
     return SIM_READY;  // unsupported
   }
 
+  String getOperator() {
+    if (!commandMode()) return "";  // Return immediately
+    sendAT(GF("MN"));
+    String res = readResponse();
+    exitCommand();
+    return res;
+  }
+
+ /*
+  * Generic network functions
+  */
+
   RegStatus getRegistrationStatus() {
     if (!commandMode()) return REG_UNKNOWN;  // Return immediately
 
     sendAT(GF("AI"));
     String res = readResponse();
-    RegStatus stat;
+    char buf[3] = {0,};  // Set up buffer for response
+    res.toCharArray(buf, 3);
+    int intRes = strtol(buf, 0, 16);
+    RegStatus stat = REG_UNKNOWN;
 
     switch (beeType){
       case XBEE_WIFI: {
-        if(res == GF("0"))  // 0x00 Successfully joined an access point, established IP addresses and IP listening sockets
-          stat = REG_OK_HOME;
-        else if(res == GF("1"))  // 0x01 Wi-Fi transceiver initialization in progress.
+        if(intRes == 0x00)  // 0x00 Successfully joined an access point, established IP addresses and IP listening sockets
+          stat = REG_OK;
+        else if(intRes == 0x01)  // 0x01 Wi-Fi transceiver initialization in progress.
           stat = REG_SEARCHING;
-        else if(res == GF("2"))  // 0x02 Wi-Fi transceiver initialized, but not yet scanning for access point.
+        else if(intRes == 0x02)  // 0x02 Wi-Fi transceiver initialized, but not yet scanning for access point.
           stat = REG_SEARCHING;
-        else if(res == GF("13")) { // 0x13 Disconnecting from access point.
-          sendAT(GF("NR"));  // Do a network reset; the S6B tends to get stuck "disconnecting"
+        else if(intRes == 0x13) { // 0x13 Disconnecting from access point.
+          sendAT(GF("NR0"));  // Do a network reset; the S6B tends to get stuck "disconnecting"
+          waitResponse(5000);
           writeChanges();
           stat = REG_UNREGISTERED;
         }
-        else if(res == GF("23"))  // 0x23 SSID not configured.
+        else if(intRes == 0x23)  // 0x23 SSID not configured.
           stat = REG_UNREGISTERED;
-        else if(res == GF("24"))  // 0x24 Encryption key invalid (either NULL or invalid length for WEP).
+        else if(intRes == 0x24)  // 0x24 Encryption key invalid (either NULL or invalid length for WEP).
           stat = REG_DENIED;
-        else if(res == GF("27"))  // 0x27 SSID was found, but join failed.
+        else if(intRes == 0x27)  // 0x27 SSID was found, but join failed.
           stat = REG_DENIED;
-        else if(res == GF("40"))  // 0x40 Waiting for WPA or WPA2 Authentication.
+        else if(intRes == 0x40)  // 0x40 Waiting for WPA or WPA2 Authentication.
           stat = REG_SEARCHING;
-        else if(res == GF("41"))  // 0x41 Device joined a network and is waiting for IP configuration to complete
+        else if(intRes == 0x41)  // 0x41 Device joined a network and is waiting for IP configuration to complete
           stat = REG_SEARCHING;
-        else if(res == GF("42"))  // 0x42 Device is joined, IP is configured, and listening sockets are being set up.
+        else if(intRes == 0x42)  // 0x42 Device is joined, IP is configured, and listening sockets are being set up.
           stat = REG_SEARCHING;
-        else if(res == GF("FF"))  // 0xFF Device is currently scanning for the configured SSID.
+        else if(intRes == 0xFF)  // 0xFF Device is currently scanning for the configured SSID.
           stat = REG_SEARCHING;
         else stat = REG_UNKNOWN;
         break;
       }
       case XBEE_CELL: {
-        if(res == GF("0"))  // 0x00 Connected to the Internet.
-          stat = REG_OK_HOME;
-        else if(res == GF("22"))  // 0x22 Registering to cellular network.
+        if(intRes == 0x00)  // 0x00 Connected to the Internet.
+          stat = REG_OK;
+        else if(intRes == 0x22)  // 0x22 Registering to cellular network.
           stat = REG_SEARCHING;
-        else if(res == GF("23"))  // 0x23 Connecting to the Internet.
+        else if(intRes == 0x23)  // 0x23 Connecting to the Internet.
           stat = REG_SEARCHING;
-        else if(res == GF("24"))  // 0x24 The cellular component is missing, corrupt, or otherwise in error.
+        else if(intRes == 0x24)  // 0x24 The cellular component is missing, corrupt, or otherwise in error.
           stat = REG_UNKNOWN;
-        else if(res == GF("25"))  // 0x25 Cellular network registration denied.
+        else if(intRes == 0x25)  // 0x25 Cellular network registration denied.
           stat = REG_DENIED;
-        else if(res == GF("2A")) {  // 0x2A Airplane mode.
+        else if(intRes == 0x2A) {  // 0x2A Airplane mode.
           sendAT(GF("AM0"));  // Turn off airplane mode
+          waitResponse();
           writeChanges();
           stat = REG_UNKNOWN;
         }
-        else if(res == GF("2F")) {  // 0x2F Bypass mode active.
+        else if(intRes == 0x2F) {  // 0x2F Bypass mode active.
           sendAT(GF("AP0"));  // Set back to transparent mode
+          waitResponse();
           writeChanges();
           stat = REG_UNKNOWN;
         }
-        else if(res == GF("FF"))  // 0xFF Device is currently scanning for the configured SSID.
+        else if(intRes == 0xFF)  // 0xFF Device is currently scanning for the configured SSID.
           stat = REG_SEARCHING;
         else stat = REG_UNKNOWN;
           break;
@@ -446,18 +501,6 @@ public:
     return stat;
   }
 
-  String getOperator() {
-    if (!commandMode()) return "";  // Return immediately
-    sendAT(GF("MN"));
-    String res = readResponse();
-    exitCommand();
-    return res;
-  }
-
- /*
-  * Generic network functions
-  */
-
   int getSignalQuality() {
     if (!commandMode()) return 0;  // Return immediately
     if (beeType == XBEE_WIFI) sendAT(GF("LM"));  // ask for the "link margin" - the dB above sensitivity
@@ -473,19 +516,42 @@ public:
 
   bool isNetworkConnected() {
     RegStatus s = getRegistrationStatus();
-    return (s == REG_OK_HOME || s == REG_OK_ROAMING);
+    return (s == REG_OK);
   }
 
   bool waitForNetwork(unsigned long timeout = 60000L) {
+    commandMode();
     for (unsigned long start = millis(); millis() - start < timeout; ) {
-      if (isNetworkConnected()) {
+      sendAT(GF("AI"));
+      String res = readResponse();
+      char buf[3] = {0,};  // Set up buffer for response
+      res.toCharArray(buf, 3);
+      int intRes = strtol(buf, 0, 16);
+      if (intRes == 0) {
+        exitCommand();
         return true;
       }
       delay(250);
     }
+    exitCommand();
     return false;
   }
 
+  String getLocalIP() {
+    if (!commandMode()) return "";  // Return immediately
+    sendAT(GF("MY"));
+    String IPaddr; IPaddr.reserve(16);
+    // wait for the response - this response can be very slow
+    IPaddr = readResponse(30000);
+    exitCommand();
+    IPaddr.trim();
+    return IPaddr;
+  }
+
+  IPAddress localIP() {
+    return TinyGsmIpFromString(getLocalIP());
+  }
+
   /*
    * WiFi functions
    */
@@ -513,27 +579,18 @@ fail:
   }
 
   bool networkDisconnect() {
-    return false;  // Doesn't support disconnecting
-  }
-
-  String getLocalIP() {
-    if (!commandMode()) return "";  // Return immediately
-    sendAT(GF("MY"));
-    String IPaddr; IPaddr.reserve(16);
-    // wait for the response - this response can be very slow
-    IPaddr = readResponse(30000);
+    if (!commandMode()) return false;  // return immediately
+    sendAT(GF("NR0"));  // Do a network reset in order to disconnect
+    int res = (1 == waitResponse(5000));
+    writeChanges();
     exitCommand();
-    return IPaddr;
-  }
-
-  IPAddress localIP() {
-    return TinyGsmIpFromString(getLocalIP());
+    return res;
   }
 
   /*
    * GPRS functions
    */
-  bool gprsConnect(const char* apn, const char* user = "", const char* pw = "") {
+  bool gprsConnect(const char* apn, const char* user = "", const char* pwd = "") {
     if (!commandMode()) return false;  // Return immediately
     sendAT(GF("AN"), apn);  // Set the APN
     waitResponse();
@@ -542,19 +599,29 @@ fail:
     return true;
   }
 
-  bool gprsDisconnect() {  // TODO
-    return false;
+  bool gprsDisconnect() {
+    if (!commandMode()) return false;  // return immediately
+    sendAT(GF("AM1"));  // Cheating and disconnecting by turning on airplane mode
+    int res = (1 == waitResponse(5000));
+    writeChanges();
+    sendAT(GF("AM0"));  // Airplane mode off
+    waitResponse(5000);
+    writeChanges();
+    exitCommand();
+    return res;
+  }
+
+  bool isGprsConnected() {
+    return isNetworkConnected();
   }
 
   /*
    * Messaging functions
    */
 
-  void sendUSSD() {
-  }
+  void sendUSSD() TINY_GSM_ATTR_NOT_AVAILABLE;
 
-  void sendSMS() {
-  }
+  void sendSMS() TINY_GSM_ATTR_NOT_IMPLEMENTED;
 
   bool sendSMS(const String& number, const String& text) {
     if (!commandMode()) return false;  // Return immediately
@@ -577,6 +644,21 @@ fail:
       return false;
   }
 
+  /*
+   * Location functions
+   */
+
+  String getGsmLocation() TINY_GSM_ATTR_NOT_AVAILABLE;
+
+  /*
+   * Battery functions
+   */
+
+  uint16_t getBattVoltage() TINY_GSM_ATTR_NOT_AVAILABLE;
+
+  int getBattPercent() TINY_GSM_ATTR_NOT_AVAILABLE;
+
+protected:
 
 private:
 
@@ -590,8 +672,9 @@ private:
     {
       sendAT(GF("LA"), host);
       while (stream.available() < 4) {};  // wait for any response
-      strIP = streamReadUntil('\r');  // read result
-      // DBG("<<< ", strIP);
+      strIP = stream.readStringUntil('\r');  // read result
+      strIP.trim();
+      DBG("<<< ", strIP);
       if (!strIP.endsWith(GF("ERROR"))) gotIP = true;
       delay(100);  // short wait before trying again
     }
@@ -644,29 +727,9 @@ public:
 
   /* Utilities */
 
-  template<typename T>
-  void streamWrite(T last) {
-    stream.print(last);
-  }
-
-  template<typename T, typename... Args>
-  void streamWrite(T head, Args... tail) {
-    stream.print(head);
-    streamWrite(tail...);
-  }
-
-  int streamRead() { return stream.read(); }
-
-  String streamReadUntil(char c) {
-    TINY_GSM_YIELD();
-    String return_string = stream.readStringUntil(c);
-    return_string.trim();
-    return return_string;
-  }
-
   void streamClear(void) {
     TINY_GSM_YIELD();
-    while (stream.available()) { streamRead(); }
+    while (stream.available()) { stream.read(); }
   }
 
   bool commandMode(int retries = 2) {
@@ -677,8 +740,8 @@ public:
       // Cannot send anything for 1 "guard time" before entering command mode
       // Default guard time is 1s, but the init fxn decreases it to 250 ms
       delay(guardTime);
-      streamWrite(GF("+++"));  // enter command mode
-      // DBG("\r\n+++");
+      stream.print(GF("+++"));  // enter command mode
+      DBG("\r\n+++");
       success = (1 == waitResponse(guardTime*2));
       triesMade ++;
     }
@@ -699,16 +762,18 @@ public:
   }
 
   String readResponse(uint32_t timeout = 1000) {
+    TINY_GSM_YIELD();
     unsigned long startMillis = millis();
     while (!stream.available() && millis() - startMillis < timeout) {};
-    String res = streamReadUntil('\r');  // lines end with carriage returns
-    // DBG("<<< ", res);
+    String res = stream.readStringUntil('\r');  // lines end with carriage returns
+    res.trim();
+    DBG("<<< ", res);
     return res;
   }
 
   template<typename... Args>
   void sendAT(Args... cmd) {
-    streamWrite("AT", cmd..., GSM_NL);
+    stream.print("AT", cmd..., GSM_NL);
     stream.flush();
     TINY_GSM_YIELD();
     // DBG("### AT:", cmd...);
@@ -731,7 +796,7 @@ public:
     do {
       TINY_GSM_YIELD();
       while (stream.available() > 0) {
-        int a = streamRead();
+        int a = stream.read();
         if (a <= 0) continue; // Skip 0x00 bytes, just in case
         data += (char)a;
         if (r1 && data.endsWith(r1)) {
@@ -767,7 +832,7 @@ finish:
       data.replace(GSM_NL GSM_NL, GSM_NL);
       data.replace(GSM_NL, "\r\n    ");
       if (data.length()) {
-        // DBG("<<< ", data);
+        DBG("<<< ", data);
       }
     }
     return index;
@@ -787,7 +852,7 @@ finish:
     return waitResponse(1000, r1, r2, r3, r4, r5);
   }
 
-private:
+protected:
   int           guardTime;
   XBeeType      beeType;
   Stream&       stream;