Wear OS Center - Wear OS Center – Android Wear Apps, Games, and News is an all-in-one launcher for your smartwatch that delivers all your Android Wear apps and watches faces all in a single place.
Fitbit Charge - Activity and sleep tracking wristband
wasp-os - Firmware for smart watches based on the nRF52 family of microcontrollers (including Pine64 PineTime)
Moto 360 - The round smart watch is finally here.
InfiniTime - InfiniTime is an open-source, C++-based firmware OS specifically made for the PineTime smartwatch.
Apple Watch Series 3 - Apple's newest internet-connected smartwatch