Inside the Arduboy is an nRF51822 – a chipset with Bluetooth Low ... notifications from a phone, with the ability to reply to these notifications. The enclosure for the ring is rather interesting.

The ‘ORII’ smart ring uses Bluetooth connectivity to allow users to control their smartphones ... listen to playback of what is running on the phone — call, music or video — by simply ...

[Phil] decided he would rather ditch the fob altogether and instead implemented a passive Bluetooth keyless ... it’s searching for the phone, while a solid ring means that a connection is ...