Thanks for your report. Please follow up in #219.
PS: High-quality pull requests are always welcome.
Is it possible to keep the synced contacts and calendars on the device after deleting the davdroid account?
perfect would be a dialog which asked for keeping information on the device on account deletion.
No. All contacts and events are deleted by Android when the respective account doesn’t exist anymore. If you delete an account, export the data before.
It might be possible to set the “owner account” of the contacts/events to null
instead of at.bitfire.davdroid
directly, but I don’t know if this will even work and can’t recommend to do so as it would be non-standard usage with undefined results.