Litchi Issue on DJI RM510

Help, I recently purchased Litchi from Google Play, Backed up the app as an.apks & installed it to my RC Pro remote. Installs good, But cannot verify my license as Google apps is not supported on the remote. After discovering the issue I learned that the solution was to buy again from Amazon App store. Only that server is not taking payment & got a message that theyre closing down the store later this year. What a balls up!..Can anyone help me out with a working Litchi app as seen youtube vids of Litchi working on my remote. Support to date in all honesty have been absolute rubbish.