ATT MEGA 6.3 ON STRAIGHT TALK 4.2.2 to 4.4.2 DATA ISSUE FIX
I updated my ATT SAMSUNG Mega 6.3 from andriod 4.2.2 to 4.4.2 today 6/12 and I noticed I dont have 4g anymore. Went to APN SETTINGS and seen that "Turn APN on/off" was greyed out and it was selected to off. To fix this simply create a new APN for your Straight talk service and the APN on/off will still be greyed out but selected to on now. Im sure this will work for any Android OS to 4.4.2. Thanks for looking and hope this fixes someone elses data issues.