I’m not actually using the native mobile app functionality of Adalo so I’d be a bad person to ask on this but my understanding is you should be able to publish both Android and iOS apps if you have a Pro account. Would need to have someone chime in who is doing it in practice to verify though.
I haven’t use it yet too, but have you updated your database schema for the new version of the app? And have you tried to remove the previous version, clear cache et reinstall the new version? I don’t think that would solve the issue you have, but that could provide inputs for investigation : either the new APK has a problem, either this situation is due to the APK version migration.
What I meant is, between your last version and your current version, have you changed the app collection(s)? These collections are what I called “the app database”.