I guess you can make at least 2 things:
1. Try to check if this connection (via mobile data) works in other apps, i.e. in simple web-browser.
2. You will need Android Debug Bridge (ADB) to collect logs from your device. Plug your phone into PC via USB cable, allow USB debugging in Developer settings, then run "adb logcat > log.txt" in the command line and run your app. It will collect all logs from your device and save them into log.txt file, where you can possibly find logs related to your issue.
06-10-2016 03:40 AM