The Keilton app requires Bluetooth 4.1 hardware or later on your device in order to work properly. This is because the app uses BLE (Bluetooth Low Energy) to communicate with Keilton devices. Phones with Bluetooth hardware earlier than 4.1 will not work correctly. Apple Devices:The Keilton app is compatible with most iPhones and iPads using… Read more What phone models are supported by the APP?