However I would have thought you could send steps via advertising relatively easily if you wanted - I don't see the reset at midnight being a big issue.
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.
Best bet is to look at the interface html in https://github.com/espruino/BangleApps/tree/master/apps/recorder
You have to read the contents of the storage file, which you can do with code like this: https://github.com/espruino/EspruinoAppLoaderCore/blob/59f80bb52a38da12cb272f9106cb3951b49dab2e/js/comms.js#L394
However I would have thought you could send steps via advertising relatively easily if you wanted - I don't see the reset at midnight being a big issue.