The Smart Ring Is A Fashionable And Wearable Electronic Product Which Is Able To Connect With A Smartphone Through Near Field Communication (Nfc) To Complete Function Performing And Data Sharing. Designed With High-level Water Resistance, It Can Be Used Without Any Power Supply. Embedded With Nfc Chip, It Can Only Be Connected To A Smartphone With Nfc Function. For iPhone, download the application. NFC. cool From the Apple Store to identify the ring and use it For Android mobile, download the application. TagWriter From Google Play Store to identify and use the ring The programs are not free.