Use APKPure App
Get 4G LTE switcher old version APK for Android
This app is useful if your phone doesn't have only 4G option
If there is no 4G compatibility in your mobile then mostly the device will work on 3G network. In other cases the default settings will be 3G so inorder to switch it to LTE or VOLTE then this app will be very useful.This app doesnt have many ads .User friendly,easy to use , best material design , compatible with almost all android devices.