If the XING app doesn't work as expected, you should usually be able to fix that by:
- logging out and in again.
- reinstalling the app (uninstall it and download it again from the App Store.
If this doesn't help, please let us know about it via the contact form. Include in your message:
- which iPhone or iPad you're using
- which version of iOS you’re using
- which version of the XING iOS app you’re using
You should inform us too whether or not your device has been jailbroken(if you don't know what this means, then your device will most probably not have been jailbroken.