@rfc2822 Thank you for the very immediate reply on this Saturday evening.
I just tried aCalendar+ (not open source but they seem support worthy). This is hilarious. For task support they rely on the OpenTasks app, which I’ve tested before and really disliked. The task management in aCal+ itself is very rudimentary, and basically only useful for the calendar integration. So I need another app for task management (I currently use Tasks.org), which I’d be fine with except for the fact that I now have 3 apps installed to do one job (4 if you count DAVx5). :')
It turns out to be quite the headache trying to scrub off the big Goo.
I’m often wiping phones for testing purposes. One of the first apps I install afterwards is davdroid (DAVx5 🙂 ). Having multiple accounts I would like to have the possibility to export / import not only the accounts but also all the individual calendars, address books and task lists (> 10!). If possible even saved if they are marked for synchronisation (I keep some address books only for backup).
For security reasons without passwords or only when hashed properly.