I still have the APK for one called "Backitude" and have kept migrating it for years since the disappearance of the developer.

It's nothing special, just a location tracker that logs to a file every so often based on time and/or distance moved (could also ping a URL with encoded location info instead). Basically the underlying data for location history without relying on Google. Its notable feature years ago was that it would do location 'steals' - instead of just triggering a then-expensive location check, it would grab the most current available location info as triggered by some other application and only force an update if that information was too old.