wigle.net - WiGLE (Wireless Geographic Logging Engine)
CellID Finder - Find a cell phone location using LAC/CellID, GSM BTS coordinates
RottenWifi - Rotten WiFi is public wifi and 3G Watchdog.
Mozilla Stumbler - Mozilla Stumbler is an open-source wireless network scanner that collects GPS data for the Mozilla...
OpenCellID - OpenCelliD is the largest Open Database of Cell Towers & their locations. You can geolocate IoT & Mobile devices without GPS, explore Mobile Operator coverage and more!
Android IMSI-Catcher Detector - Detect attacks of fake base stations such as IMSI-Catcher and StingRay on your GSM/UMTS network.