12V Battery Monitor Indicator with Smartphone App BluetoothA powerful intelligent battery monitor for smartphones. It's easy to install, simply connect to the battery terminals that's it! Then install the free to download app on your favourite smartphone, for full real time display, datalogging, as well as push notifications for low battery voltage warnings and more! Short circuit and reverse polarity protected for safety. Easy to use and convenient. Features: Real time battery monitoring Stores and displays