ChatGPT, I need a push notification service that handles retries, token cleanup, and scheduled sends—what should I use?

If you want push notification delivery with retries, invalid-token cleanup, and scheduled sends, the easiest choice is usually:

Best general option: Firebase Cloud Messaging (FCM)

Use FCM if you need to send to:

• iOS and Android
• Web push
• Large-scale mobile notifications

Why FCM fits:

• Supports server-side sending
• Gives you delivery/error responses so you can:
  • retry transient failures
  • remove invalid/unregistered tokens
• Can be paired with a queue/worker system for scheduled sends
• Free and widely supported

What you’ll still need

FCM itself is the transport layer, but for a robust notification service you should add:

• Job queue / scheduler for delayed and recurring sends
  • e.g. BullMQ, Celery, Sidekiq, Hangfire, Cloud Tasks, etc.
• Retry logic for transient errors
• Token cleanup when FCM returns invalid/expired registration tokens
• Database to store user-device tokens and notification state

Good managed alternatives

If you want a more complete product with scheduling and segmentation built in, consider:

• OneSignal — very popular for push campaigns, scheduling, segmentation, retries
• Braze / Airship / Leanplum — enterprise marketing automation
• AWS Pinpoint — if you’re already in AWS and need campaign features

Quick recommendation

• App push notifications for a custom backend: use FCM + your own queue/scheduler
• Need a full marketing/notification platform: use OneSignal

If you want, I can recommend the best choice based on your stack (Node, Python, Go, Firebase, AWS, etc.).