Free download Switch Network Type 2G / 3G APK for Android, PC. Latest version is 1.0, update at October 5, 2015
Switch Network Type 2G / 3G version 1.0 is only one variant.
This app/shortcut opens directly the settings app of mobile network settings to switch between "2G" and "allow 3G" networks (e.g. to save battery). A direct switch is sadly not possible....