When using, first open the mobile phone APP and pair it with the anti-lost device. If the small anti-lost device and the key are hung together, the user needs to find the key, just point the phone according to the APP alarm function, the anti-lost device will be issued The sound, on the other hand, when looking for a mobile phone, you only need to click on the button on the anti-lost device. The phone will make a sound. When both Bluetooth connections are disconnected (distance away), the mobile phone and anti-loser will alarm, so as to achieve bidirectional anti-lost function At the same time, the app is also equipped with camera, video, and map positioning functions. At the same time, the APP can also support conference recording (you can't get anti-lost function when recording). It is a good companion for home travel.