If you opened a personal Google Play developer account after November 2023, you cannot publish to production until 12 testers have run a closed test for 14 consecutive days. Here is exactly how the rule works and how to satisfy it without gaming it.
I maintain both Flutter and native Java apps on the Play Store at the same time. Here is the decision framework I use on real projects, including the cases where I still reach for native Android.
Everything between a finished APK and a live Play Store listing, in the order you need it — account setup, signing, the data safety form, store listing assets, closed testing and the rejection reasons that catch people out.
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Need this done rather than explained?
I take on Flutter builds, Play Store publishing and app rescue work for clients.