A simple fix for all Samsung s2 s3 and s4 phones , including all mini versions of the range , If Phone will not lock on to gps satellites try this. Remove back of phone, then with small fine Phillips screwdriver tighten all screws on the back. Only needs gentle pressure approx 1/64 of a turn in most cases. Replace back cover. Gps should now lock on and be super accurate. Good Luck.