The application come with dual SIM Support. Only you need to download this application of 4G Only Network Mode LTE VoLTE Dual SIM Setting App and follow the instruction.
If you have a 4g sim, 4g contract, and your cel phone supports your carrier's 4g bands but you stil can't get a 4g/lte connection, you made need to enable lte mode on your modem. here's how to do it. check your current settings. this is important to retain 3g data when moving out of 4g range.
Force LTE Only - 4G LTE Mode app helps you to find and search for 4G LTE signal. Once you locked to 4G Mode, no other 2g/3g signals won't be catch by your phone so your device will always be in 4G Network.
This application or Force LTE Only - 4G Lte Mode helps people to set their mobile in 4G or LTE mode which save people from fluctuation in the network as well.