Questions about push notifications in 1.44 -> 1.46

From the DeltaChat’s fediverse account, it was stated " With the rolling 1.46 #deltachat app releases you can start chatting without a pre-existing e-mail address, and benefit from push notifications (instant message delivery) also on Android."

(and apparently IOS had push in 1.44, hence my subject)

I’m confused a bit by the wording - what’s setup in or on a chatmail server that makes it any more capable of push notifications than any regular email server? Is there something I can add to my own postfix/dovecot setup that accomplishes the same thing? (and I see upon looking that dovecot has push notification features that I honestly haven’t really dug in to before) Do the push notifications work better than DeltaChat using IMAP IDLE?


There is a new section added to the FAQ page which explains this:

Previously Delta Chat relied on IMAP push, which is fine if your phone OS doesn’t suspend background apps. This method was completely independent from Apple and Google services.

The latest change means that you will get push notifications from Apple’s or Google’s push server, but only for accounts that use a chatmail server.

Push notifications sent using Apple/Google infrastructure are delivered faster than IMAP push if your phone OS suspends background apps. If your phone OS doesn’t suspend background apps, there isn’t any advantage to using Apple/Google push services.

I assume this means that you will receive both an IMAP push and an Apple/Google push notification for new messages if you have a chatmail account.

I’m sure it’s technically possible to make your own server do the same thing, maybe take a look at the chatmail source code and see how they implemented it there, or maybe the developers can give you more specific advice about how to do this.


yes anyone can currently replicate it by copying the chatmail configuration, so anyone can add support for their mailserver.
But there is no support for custom push services like unified push yet, there is only our relay server that supports apple production tokens, apple sandbox/development tokens and newly added Google FirebaseCloudMessaging tokens for android devices with play services or microG.

In a future iteration of the protocol it would be nice to have a dovecot configuration and protocol/api that supports arbitrary push endpoints.
This would enable other email clients or forks of DeltaChat to make also work with those email/chatmail servers and would open the doors for the android client to add a config option for a custom unified push endpoint.
We did not go for that solution yet, because it is technically more complex as you’d need to validate the endpoints the client provides, so the protocol can not be abused to DOS someone over your email server.