The flashing triangle is specific to Android phone. It means that the system has been tampered and the files have been modified. In this case, I recommend that you use Triangle Away. First root your phone then install the application and launch it. Apply the patch and the triangle away will wipe the icon. It will restore original firmware status for the phone allowing you to call or do whatever you want. I have tested the application on my S3 for multiple times and it worked great. It's also risk- free, but make a backup with Kies before doing this.