GSM Field Test

What is it?

GSM Field Test is a specialized application for Android devices that allows to create coverage map of GSM/UMTS/LTE networks. It displays a map with markers which color depends on a level of signal measured by your phone in a given location.


GSM Field Test helps to determine areas with the best coverage of mobile phone network. The app creates a map with a set of markers. Green markers are placed in locations with a high signal strength; red markers indicate that coverage is rather bad. In the alternative color scheme a poor signal is marked in blue.

There may be two sources of maps: Google Maps or OpenStreetMap.

A new marker is put to the map if the following conditions are met:

  • the location is determined
  • the location accuracy is less than the limit set in preferences
  • distance between the location and the previous marker is bigger than value set in preferences

Map with markers can be saved as a PNG file to a SD card. You can also export markers as KML file (for Google Earth) or CSV file (comma-separated values).

DB Manager allows to import base station locations. The app supports CLF format of version 3.0. You can find more details about CLF files for import on this page.

Supported languages

  • Czech
  • English
  • French
  • German
  • Russian
  • Spanish

Please, help to translate the application user interface on other languages! Mail to


  • Q: Why does the app work incorrectly on Dual SIM phones? A: Android provides data only about the SIM plugged into the first slot.
  • Q: Can the app show channel number/frequency/timing advance? A: Unfortunately Android SDK doesn't provide this information.

Have a question? Use the form on the about page and submit it!


  • 3.0 (released 2014/11/15) - New GUI
    - Database Manager
    - Alternative color scheme
    - Spanish, German, French and Czech translation
    - Bug fixes
  • 1.6 (released 2014/02/13) - New design
    - More data for a marker
    - Export to CSV
    - Bug fixes
  • 1.3 (released 2013/05/29) - Work in background
    - Bug fixes
  • 1.2 (released 2013/05/14) - Bug fixes for LTE devices
    - New menu icons
  • 1.1 (released 2013/05/05) - Support of OpenStreetMap
    - Cell strength is displayed over a map
    - App is available on Samsung devices