Got the logcat finally.I see, i would really need to see the logcat of your device. You should not need root for that you only need a pc with adb working, then typeand let it run some time. This should throw out a nice mylog.txt in your current folder.Code:adb logcat > mylog.txt
Also try restarting your phone and please check if your phone connects to the cameras wifi in your android settings -> wifi! For me this was the "main" problem of black background and sometimes only a "loading...." screen.
Best Regrads
https://drive.google.com/open?id=0B-lAyfkO-k_GbUMxODZtQ1hieWc
Thanks!