Go App 3.1.18 FCC -> DJI Go App 3.1.18 FCC - Kopter - Support Forum
Go App 4.1.22 FCC -> Go App 4.1.22 FCC Mode. - Kopter - Support Forum
If you need both version (original DJI and the modded one) on your device, use AppCloner
App Cloner Guide
This process will allow you to have 2 versions of...