I'm not sure of the technical feasibility of this, but I'd absolutely love for there to be Push email sync cability in the Email app. For some workloads, this can actually SAVE the user battery life (awesome stuff). It is also great for business users or people who rely upon emails for "serious" stuff, as having a polling delay can be costly. Also, the other platforms all support this so FFXOS should try to make parity on this feature.
Unfortunately there are some technical issues. In most cases push email is just a long-lived TCP connection (see https://bugzilla.mozilla.org/show_bug.cgi?id=991024#c1) which can be power hungry/flakey or involves proprietary protocols that are vendor specific and can't be hooked up to the Simple Push API. For example, Apple's iOS device can do fancy push because of Apple's "XAPPLEPUSHSERVICE" pseudo-standard. However it's hardcoded to contact Apple's servers. In many other cases mail providers provide custom apps that can do true push notifications (gmail, fastmail, others) but which aren't available over standard IMAP. Our plan for IMAP has been to try and get a standard created. :brong from fastmail has indicated they have push notifications for their app/etc. and I think that's probably our best chance for moving forward on a mechanism that we can hook up to the push notification system used by Firefox OS. So I think for many cases the other platforms are doing the proprietary thing or are just keeping TCP connections alive for a long time. If you're able to look into what any of them are doing and report back here, that would be super handy. We're still pretty resource-constrained and playing catch-up, so I haven't had time to look into whether there are other shenanigans we can play to get push notifications from places. Prior to me learning about fastmail's push notifications, the plan was to create a dovecot example plugin and possibly Zimbra to try and push forward with standardization and some limited adoption.
Has there been any advance on this? Either regarding the fastmail approach or dovecot plugin, and associated standardisation.
Here are some of the alternatives that I see for push email: Fastmail's implementation: http://jmap.io/ It seems to me that ActiveSync might be a good interim alternative too since it's already supported by the email client, is widely used, and there are already open source implementations available for the server side: https://z-push.org/
No progress; if you have any time to assist, it would definitely appreciated. Note that ActiveSync, like IMAP IDLE, depends on long-lived connections, it's just an HTTPS long-poll instead of a TCP connection. We need server support where the server supports generating a notification to an arbitrary HTTP(S) URL to accomplish our goals of low-power, low-latency, and high reliability.