Thanks for the update Nicolai!

My reports:
Contacts, Calendar, searched existing name:
It showed contact and birthday (calendar), no crash
Contacts, Calendar, searched 'flurk' (nonsense):
No results, empty screen, no crash

Contacts, Conversations, Calendar, searched existing text:
Crash after result screen filled up (which is after 5 results)

Contacts, Conversations, Calendar, searched 'flurk':
No results, app crashes after a few seconds (it does look like it's searching before crash, load animation circle is shown in top bar)

Case sensitivity had no influence on the above

Hope it helps!