I have an app I use very occasionally that starts every time I connect to the internet even though I am not intending to use it. It has lots of map files it has downloaded and other associated files that I would like to preserve in place until the time I want to use the app. I've talked with the developers and they ignored or did not understand my problem.
My thought for a solution: make a dummy app that would install over the existing app and leave all the parts in place. When I want to use the app, I could reinstall the app.
Is it possible to make a dummy app that would install over the existing app and preserve all the app's files and settings?
No, I don't think something like that is possible. Partial solution: Settings -> Network & Internet -> Data usage -> App data usage -> <select app> -> turn "Background data" off. That will at least prevent the app from going online over mobile networks. I don't think it's possible to prevent it from going online over Wifi on stock Android (there are proprietary additions from some manufacturers that allow this as well).
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