You can use the [ntfy Android App](https://play.google.com/store/apps/details?id=io.heckel.ntfy) to receive
notifications directly on your phone. Just like the server, this app is also [open source](https://github.com/binwiederhier/ntfy-android).
Since I don't have an iPhone or a Mac, I didn't make an iOS app yet. I'd be awesome if [someone else could help out](https://github.com/binwiederhier/ntfy/issues/4).
<figcaption>Turning off the persistent instant delivery notification</figcaption>
</figure>
### Limitations without instant delivery
Without instant delivery, **messages may arrive with a significant delay** (sometimes many minutes, or even hours later). If you've ever picked up your phone and
suddenly had 10 messages that were sent long before you know what I'm talking about.
The reason for this is [Firebase Cloud Messaging (FCM)](https://firebase.google.com/docs/cloud-messaging). FCM is the
*only* Google approved way to send push messages to Android devices, and it's what pretty much all apps use to deliver push
notifications. Firebase is overall pretty bad at delivering messages in time, but on Android, most apps are stuck with it.
The ntfy Android app uses Firebase only for the main host `ntfy.sh`, and only in the Google Play flavor of the app.
It won't use Firebase for any self-hosted servers, and not at all in the the F-Droid flavor.