The app then allows you to replay these log files in such a way that your phone and other apps running on it are fooled into thinking you are retracing your steps when you could be sitting somewhere else, perhaps without any GPS signal available.
Because the log files are in a simple CSV format, you can edit them with any text editor or spreadsheet program to modify the GPS tracks. You are also able to share your tracks with friends via email or any other method of file-sharing, so that if you have recorded a really interesting or useful track they can use GPS virtually retrace your steps on their device.
Any device with GPS signal can record GPS data. GPS (or other) location needs to be enabled, and there needs to be sufficient GPS signal to attain a fix.
The GPS data is currently saved in a simple text format. Future versions of the app will include an option to save in a standard GPS track format that can be viewed or manipulated with 3rd Party Tools.
To replay GPS you need to either:
1. Enable Developer Settings on your device, and then enable Mock Locations, or
2. Have a Rooted device and use a tool such as Root Explorer or APP2ROM to install GPS Replay as a System / Privileged App.
3. Replay often works better if you disable GPS on your device before starting playback, however some apps insist that device GPS is enabled.
Note that GPS Replay will prompt you by taking you to the Developer Settings in order to Enable Mock Locations if neither of the above has been done already.
Use Mock GPS Locations with Android User Profiles
Some applications detect if the Mock Locations setting has been enabled and then not work as desired.
To get around such detection you can either root your device, or use a version of Android that has User Profiles enabled (stock Android for most Android tablets do). Then run the GPS Replay in the main "Owner" User Profile with Mock Location setting enabled and then switch to a different User Profile to run the target application.