[sanmanc]

One of the things I learned using back up was to back up every time before I installed a new app. That way if a new app messed up the OS I could restore to the previous back. My suggestion is hard reset then install an app and test. If it works back then install a second app. Continue until you find the culprit. This can be a long trouble shooting step but at least you will know what may be causing your problem.