I think Lock 3G setting is veri important in low 3G signal area. its about lower than 50 %. so the internet will not disconnection and the speed will stable without not responding. and the most important is we can save the batteries. because its not always search the strongest signal.
How to ;
1. Go tho Call phone
2. tap *#*#4636#*#* and then tap phone informationm
3. scroll down. and choose WCDMA Only on set preferred network.
If You still Confused. i was create tutorial video below. check it out !
ConversionConversion EmoticonEmoticon