A comparison of WiFi, Bluetooth, ZigBee, GSM, and RF by range, speed, and power consumption, to help you pick the right wireless method.
Use nearby Wi-Fi network scanning and a cloud geolocation service to estimate a geographic location with NodeMCU, no GPS module required.
Build a simple web server on an ESP8266 module to show a temperature reading on a local web page, with a technical note on voltage compatibility between Arduino and the module.