Android IMSI-Catcher Detector - Detect attacks of fake base stations such as IMSI-Catcher and StingRay on your GSM/UMTS network.
WiFi Map - A crowdsourced list of routers and passwords
CellID Finder - Find a cell phone location using LAC/CellID, GSM BTS coordinates
Café Wifi Search 🔍 - Find great cafés to work from, worldwide.
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!
Instabridge - Crowdsourced free wifi (now on Android)