Seems to be a duplicate of https://forums.bitfire.at/post/9654, please follow up there.
Currently it seems to help to uninstall DAVdroid and install it again.
If at least one contact has at least one relationship specified, the app crashes whenever it syncs. There’s a “RELATED” field in vCards so this should not happen, as far as I know.
Can’t reproduce that issue with CyanogenMod Android 4.4.4. Please provide detailed steps to reproduce (what relation to enter etc.).
Duplicate of #547?
Please check whether this issue is still present with DAVdroid 0.8.1.
I guess this was a duplicate of #547, so I’ll close this issue now. If this problem happens for DAVdroid 0.8.1+, please post here again.