PineTime (Pine64 Watch) Trials

• Long time wish to build a smart watch. Experimented with various platforms, not built anything usable yet.
• Many opensource variants: watchy, openwatch, pinetime, etc.
• Pinetime is by the Pine64 Organisation Pine64 Org. They make many open source products like laptops, phones, watches, SBCs, etc.
• The Pine64 forum has a watch called the Pinetime. It looks nicely packaged and so wanted to see if its suitable for everyday use. More info here PineTime
• It is an NRF52 based chipset with an IPS display and chinese sensors for heart rate and step counting.
• They have an FreeRTOS based OS called the Infinitime . It was WIP then (Mar2021), so many features were under development and also the UI was rudimentary.
• At about the same time there was another micropython based OS called WaspOS which was under active development. 
• Downloaded this and generated the OS.
• The advantage is that one can just write micropython apps and download to this board. No classical embedded development necessary.
• Using the standard Nordic Semiconductor tools both the OSes were flashed and various features explored.
• Observations:
• The apps were basic, back then in 2021.
• Most importantly the values of the step counter and heart rate sensor were compared against a FitBit and a MAX30102 based homebrew device. The default values had many variations from the other reference devices. Maybe time could have been invested to make it rugged but then there were more accurate options so this was discontinued.
• Interestingly it has Notifications support with an Android Mobile phone using Gadgetbridge. So this could be used for writing cool watch based control things.
• Below are some images/videos of the watch in operation.