Thank you all for the reports.
This is not related to MetaChat, no code has changed but the compiler changed and thus the app runs into a dead end.
This does not happen on OpenChat and GroupChat because that´s a complete different pair of shoes.
This bug only happens on some devices, i never received it on my 3 real devices: iPhone 5, iPad Air 2, iPhone 5s
Right now i am investigating the problem with the few crash reports i received and where i have to dig thru tons of nonsense lines to find the error.
Please bear with me while i´m waiting for replies from Microsoft, who do not answer question or bug reports on the fly.