Mi Fit - Mi Fit is a band to monitor your health and fitness level on daily basis.
Tep - Fitness tracker meets tamagotchi. Don't starve it!
Gadgetbridge - A free and cloudless replacement for your gadget vendors' closed source Android applications.
HB Ring - See and feel the real-time heartbeat of your loved one
Garmin Vivofit 2 - Garmin Vivofit 2 is highly strict activity and fitness tracker that motivate you to get up and get moving.
Nimb - Smart ring with a panic button