In order to give you an update on this matter. We’re in contact with the Mirakel developers and sent them some suggestions that are needed to integrate sync compatibility into DAVdroid. So it will still take some time…
Restrict time range of syncronisation
as written here
This would be nice. Syncing my calendar takes quite a bit of time (30-60 seconds), presumably because it’s syncing years worth of information every time?
Ideally the initial (and perhaps a manual “full/force resync”) sync would sync the complete calendar history, but automatic syncs would only sync events >= one week ago or so.
It doesn’t sync the information every time but at least the ETag (hash) for every iCal.
Partial syncs will be a very challenging task, but I will have a look at it when other things are stable.