Well, if you want bare nrf52 module then perhaps just get one, these are like $4.5 on aliexpress :-)
You mean pointless as fitness tracker to stay healthy or as Espruino board?
I don't know how 5v input for charging could be also power output, possibly not. As for not used gpios, depends what you want to use, ther is reset pin (gpio 21), you can disconnect heartrate sensor and have plenty of gpios (test points are below LCD) or there is this unpopulated area near CPU which can host some spare GPIOs, see the photos.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Well, if you want bare nrf52 module then perhaps just get one, these are like $4.5 on aliexpress :-)
You mean pointless as fitness tracker to stay healthy or as Espruino board?
I don't know how 5v input for charging could be also power output, possibly not. As for not used gpios, depends what you want to use, ther is reset pin (gpio 21), you can disconnect heartrate sensor and have plenty of gpios (test points are below LCD) or there is this unpopulated area near CPU which can host some spare GPIOs, see the photos.