IOS 1.7.3 was just pushed out, this fixes a cash when notifications arrive and the app is open. This also is the first release under our new openHAB Foundation account, which you can read more about on @Kai 's recent post Ready to join the openHAB Foundation? .
Because of the change to our new Foundation account, we also needed to regenerate our Apple push notification (APN) certificates. Those are now out on my.openhab.org and will be compatible with the 1.7.3 release. This also means notifications may not work until to you upgrade to this latest release.