CalDAV-Sync
From dmfswiki
CalDAV-Sync is a CalDAV client for Android to synchronize events. Due to its implementation as sync adapter it integrates seamlessly with the default calendar app.
known issues
- Time zones are not handled yet. All times should be imported correctly but are written relative to UTC on the server. So times are still correct but time zone information is lost.
- Attendees are not synced at all.
- May crash if the phone's orientation is changed during account setup.
- many more, I'll add them here during the next days