Instrument the pipeline
Track drop-offs from API send to device receipt with Watch.Dog synthetics on APNs and FCM.
Alert when providers throttle or when device acknowledgements dip by region.
If you cannot see end-to-end push delivery, you cannot claim notification uptime.
Design graceful fallback
Use in-app inbox or SMS as a backup for critical notifications during provider incidents.
Cache retries with exponential backoff and device state awareness to avoid spamming.
Test on real devices
Include mobile labs in your monitoring plan to see how app states, OS versions, and battery savers impact delivery.
Mirror production feature flags in test apps to validate routing changes.