Duet, and the PROTAG app, is an entire eco-system built upon latest Bluetooth 4.0 Low Energy technology, to prevent you from losing your phone. It’s your phone’s ever watchful buddy. It is a small (2mmx2mm) tag that attaches to your keychain, bag, wallet or slips into your pocket. It works with both iOS and Android operating systems. Your Duet looks out for your smartphone – and vice versa – and you are notified immediately by Duet’s built-in alarm if you have left your smartphone behind (within a 10 meter range). In enclosed areas such as your house or office, you can also press a button on Duet to ring your phone, allowing you to hear and find it quickly.