Debugging React Native Bugs That Only Happen on Client Devices

The HAB1 Azan Bug

On iOS, Azan notifications would not play when the app was backgrounded. Multiple senior developers had tried and failed to fix it.

My Debugging Steps

1. Reproduce reliably

• Exact iOS version
• App state (foreground, background, terminated)
• Notification type

1. Read the platform docs deeply

Especially around:

• Audio sessions
• Background modes
• Notification payload constraints

1. Build a Minimal Repro App

Strip everything:

• One screen
• One button to schedule a notification
• Simple sound file

Once that worked, I ported the fix back into the main app.

Lessons

• For platform-specific bugs, small repros beat big logs
• Sometimes the real solution is understanding OS behavior, not adding more code