What is Push and why do I need it?

TLDR;

Get updates for your contacts/events/tasks/notes instantly on your mobile device instead of polling the server in regular intervals like once an hour.

Requirements:

DAVx5: minimal version DAVx5 4.5 (released June 2025)
FCM (pre-installed on devices with Google Play Store) or any UnifiedPush distributor app (ntfy, Conversations, the NextPush app for Android, Mozillas Sunup, etc).
The server must support WebDAV Push.

More Details

WebDAV Push is a very new addition to the WebDAV ecosystem and extends the WebDAV Standard with the ability to make synchronization in near-realtime. So if a file on the WebDAV server is added, changed or deleted you will receive this instantly also on your mobile devices via DAVx5.

This is especially useful for Contacts, Events and Tasks all of which DAVx5 offers synchronization for. Whenever a resource on the server changes (be it from directly changing it or if the change is being made from another device) you should get this update within a few seconds depending on network and server speed.

How-to-use in 5 steps (watch the video):

Install and activate the servers WebDAV Push extension (for example the Nextcloud dav_push app in your Nextcloud App center – minimal version 0.0.3)
If you add a new account, continue with step 3. If already have an existing DAVx5 account:
- refresh the collection list in the CalDAV/CardDAV tabs to receive the new information that the server supports WebDAV Push and check in the details view of a collection if you see either a "Server announces Push support" or "Subscribed message with a date".
If you add a fresh DAVx5 account, the capability of Push will be detected during setup.
Choose or Change the Push distributor in the DAVx5 settings at the very bottom.
To test it, add an event, contact or task on the server side and open your respective Contacts / Calendars / Tasks app on Android. You should get the change within 5 – 60 seconds (depending on network speed)

Resources for server developers:

In order to provide your users with the ability to real-time sync data from your server you can implement the WebDAV Push draft. Although it is still a draft this solution already is working in the public. You can see an implementation for example on Nextcloud where this is being solved via an app plugin that can be activated upon a users wish.

See also UnifiedPush 3: https://unifiedpush.org/ and https://codeberg.org/UnifiedPush

What's Changed since 4.4.11

New features

Add app password hint under password field by @sunkup in #1507
Support Fastmail OAuth by @rfc2822 in #1509
Support OAuth re-authorization by @rfc2822 in #1521

Bug fixes

Fix edge to edge issue by @ArnyminerZ in #1515
Delete local collection if missing remotely at delete request by @sunkup in #1512

Refactoring

Credentials / dav4jvm: store passwords as CharArray by @rfc2822 in #1483
[Lint] Convert URIs to strings using toUri() by @rfc2822 in #1506
Pass state to modal drawer for automatic back handler by @ArnyminerZ in #1495
[SyncManager]s Remove authority by @sunkup in #1491
Increase SDK to 36 by @ArnyminerZ in #1513

Other changes

Replace ical4android and vcard4android with synctools by @rfc2822 in #1519
Redact Authorization header from HTTP requests by @mbiebl in #1520
Intro / battery optimizations warning: remove Samsung; change wording from "probably" to "may" by @rfc2822 in #1532
UnknownHostException by @rfc2822 in #1535

Full Changelog: v4.4.11-ose...v4.5-ose

bitfireAT/davx5-ose v4.5-ose on GitHub