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+One capability of Tasmota is that you can connect additional things to available pins on the ESP8266 that controls these devices
+
+If a pin is defined as GPIO_USER in the module template, you can assign it one of the following functions:
+* GPIO_NONE,           // Not used
+* GPIO_DHT11,          // DHT11
+* GPIO_DHT21,          // DHT21, AM2301
+* GPIO_DHT22,          // DHT22, AM2302, AM2321
+* GPIO_DSB,            // Single wire DS18B20 or DS18S20
+* GPIO_I2C_SCL,        // I2C SCL
+* GPIO_I2C_SDA,        // I2C SDA
+* GPIO_WS2812,         // WS2812 Led string
+* GPIO_IRSEND,         // IR remote
+* GPIO_SWT1,           // User connected external switches
+* GPIO_SWT2,
+* GPIO_SWT3,
+* GPIO_SWT4,
+* GPIO_SENSOR_END
+
+
+# Examples
+
+1.    If you take a Sonoff Basic and connect a switch between pin4 (ground) and pin5 (GPIO4) of the 5 pin programming header you now have a second switch connected to the device. You can set this through the module config page or from the command line with
+    `gpio 4 switch1`
+
+    now when you hit the built-in switch you should get power1 instead of just power, and if you hit the second switch you will get power2
+    you can set the mode of each switch individually with switchmode1 or switchmode2
+
+2.    Instead of connecting a switch, you could connect a 4-pin 2.5mm jack, with the pins wired:
+    * tip pin5 (GPIO4)
+    * r1 no connection
+    * r2 pin1 (3.3v)
+    * r3 pin4 (ground)
+
+    You can then plug a sensor into the jack like you would to a Sonoff TH10/TH16 and define what sensor you have connected to GPIO4
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