store and sync user data

  android, cloud, database, ios

I am creating an Android app (using Android studio) and later an ios app. After the user has created an account They will produce a few .txt files (I guess less than 1MB per user) these files will be updated every few minutes and then have to be stored somewhere e.g. a cloud (a cloud for the app and not the user’s cloud) to sync between platforms or to restore data when reinstalling the app. So the question is what to use to accomplish that? I’m not sure what I need in this case!

Source: Android Questions