"Blinq" app need to be used with Blinq smart rings. It can provide below functions:- Smart Notification. The ring will vibrate when the phone receives incoming calls, text messages and other app notifications. - Anti-lost. The ring will vibrate when it is apart from the phone by certain distance.- SOS. In emergency, you can send text messages with your current location by continuous knocking the ring.Attention:- SOS function requires persistent location even when it is in background mode.- Continued use of GPS running in the background can dramatically decrease battery life.Use Blinq smart ring, enjoy fashion and technology.