+ Samsung Band Selection
+ speed test
2: open app Samsung Band selection => LAUNCHER BAND SELECTION
View the network in automatic mode is ok
3: open app Speed Test and try network speed
4: open app Samsung Band selection => LAUNCHER BAND SELECTION
Look at the list and select GSM/WCDMA and hide the samsung Band selection app and open the Speed Test app to try the network speed
5 : open Samsung band selection app
Look at the list and select network type " Band selection mode "
Press repeatedly on o it 5 times to 10 times and last click select network type " Automatic "
( repeatedly press "band selection mode" and last click automatically )
Open app Speed Test and try test network speed
Network speed will be very fast .
Sorry I speak English very badly
Watch the video and follow the instructions