If you want to replace Bangle.setUI it's pretty easy to do so by adding it to your boot code. Tutorial here: https://www.espruino.com/Bangle.js+Modification
Bangle.setUI
@Gordon started
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.
If you want to replace
Bangle.setUI
it's pretty easy to do so by adding it to your boot code. Tutorial here: https://www.espruino.com/Bangle.js+Modification