How to access content of the google drive app backup? I accidentally uninstalled an Android app (GPSLogger), and lost all the app data (GPS tracking files). Now I can see is an automatic backup in google drive, but the app does not recover it, when I re-install it. 

Question: Is it possible to access the backup with some ohter tools and to extract the contained files manually ?
This is a not complete answer to the above question, but just a helpful hint.
As it is stated on Android Backup Service help page


  Not all apps use Android Backup Service. Some apps may not back up and restore all data.


So you should at first check if GPSLogger utilize Android Backup Service and then try to extract backup data.

The most proved way to backup app's settings is to copy folder

/data/data/com.some_vendor.some_app


beforehand and then to restore it manually. Or use some professional tool like Titanium, of course.