The summary.
LOSING YOUR ANDROID SIGNING KEY MEANS YOU CANNOT UPDATE THE APPLICATION AT ALL
Use the platform's key management and back up credentials securely.
TEST THE RELEASE BUILD, NOT THE DEBUG BUILD
Shrinking and obfuscation break reflection-based code, and that appears only in release. Keep the mapping file for deobfuscating crash reports.
And test upgrading from the currently released version with real data — most serious release problems affect existing users, not new ones.
KEEP STORE DECLARATIONS ACCURATE AS THE APPLICATION CHANGES
Declarations inconsistent with actual behaviour are a common cause of rejection and enforcement — and account-level action affects every application you have, not only one.
Never create a new account to circumvent enforcement.
GIVE REVIEWERS WORKING TEST CREDENTIALS AND NOTES
Reviewers who cannot reach a feature reject the submission.
USE A STAGED ROLLOUT AND WATCH THE CRASH RATE
A defect can then be halted before it reaches everyone.
Remote feature flags matter because a new release takes days to arrive and some users never update.
ESTABLISH WHICH PAYMENT RULES APPLY BEFORE BUILDING
It determines whether you may use your own payment provider at all.
