fitbit - The Fitbit mobile app is for people who use Fitbit fitness trackers to keep track of their activity goals, food plans, and other fitness related things. Read more about fitbit.
wasp-os - Firmware for smart watches based on the nRF52 family of microcontrollers (including Pine64 PineTime)
HeadUp Labs - Sync your Fitbit or Apple Watch to the HeadUp Labs app & see your personalised human dashboard...
InfiniTime - InfiniTime is an open-source, C++-based firmware OS specifically made for the PineTime smartwatch.
Digifit - The Digifit ecosystem is a full suite of Apple apps that records heart rate, pace, speed, cadence...
watchOS - Apple's new OS for the Apple Watch ⌚