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Brandon Him


Creator and Tech Enthusiast


My Favorite Open-Source Projects for Fitbit Development

By Brandon Him
May 13th, 2020

​ If you know anything about me, I'm a huge advocate of open-source development. In my past life (prior to a family), I would spend every weekend at a coffeeshop building open-source projects. Overtime, I gathered over half a million downloads in my open-source projects and over 1,000 stars on GitHub.

​ Honestly, it's extremely rewarding helping others achieve at scale, especially when you combine it the community -- the end user benefits the most from it.

​ Now enough of my scpheil, here are my personal favorite OOS repositories for developing sound and robust Fitbit watchfaces and applications.

FitFont by gregoiresage

🚀 Donate to gregoirsage @


fitfont is by far my personal favorite and is truely under appreciated.

If you are new to Fitbit development, you'll discover that custom fonts are a typical challenge as you need to generate individual images per a letter. However, this repository automates that process and creates a widget for you to use quickly.

Also, it contains an API familiar to the text element but with some pretty neat extras like horizontal alignment and letterspacing.

Example Code

import { FitFont } from 'fitfont'

const statLabel = new FitFont({ 
  id: 'stat-label',
  halign: 'start',
  valign: 'middle',
  letterspacing: -1 

statLabel.text = 'Steps'

fitbit-views by SergioMorochon

fitbit-views is a simple, yet powerful module for navigating between views in your Fitbit applications. You can think of it as a router module similar to what you would typically use for any SPA application.

Example Usage

import { setup, next } from 'fitbit-views';
import HelpPage from './views/HelpPage';
import ListPage from './views/ListingPage';

    'help': HelpPage,
    'list': ListPage,

document.getElementById('helpButton').onactivate = () => {

fitbit-asap by dillpixel

Despite the drastic improvements on the messaging API (thanks to project Golden Gate), Fitbit developers all know that the messaging API is still rather finicky.

This is where fitbit-asap comes along, it's an added level of reliability by abstracting the handling of retransmits -- kind of like TCP. It also has an easy API that is identical for both companion and device side with three main API methods: send, onmessage, and cancel.

Example Code

Device (App Side)
import asap from "fitbit-asap/app";

asap.send("Knock, Knock");

asap.onmessage = message => {
  if (message === "Whose there?") {
  if (message === "Chicken Who?") {
    asap.send("Chicken Butt!!");
import asap from "fitbit-asap/companion";

asap.onmessage = message => {
  if (message === "Knock, Knock") {
    asap.send("Whose there?");
  if (message === "Chicken") {
    asap.send("Chicken Who?");

My apologies for 1st grade humor. :)

fitbit-weather by gregoiresage

By far one of our biggest feature request is weather support on watchfaces. However, instead of building out your own weather component, you really should be using a module that is robust and well-tested, this is where fitbit-weather comes into play. fitbit-weather is a library that allows you to pull weather data to display on your Fitbit watchface. It handles the geolocation, conversions of temperature between F and C, and supports 3 big weather providers.

Example Code

import * as weather from 'fitbit-weather/companion';

const config = { 
  provider: weather.Providers.openweathermap,
  apiKey : 'YOUR_KEY' 

import * as weather from 'fitbit-weather/app';

weather.fetch(30 * 60 * 1000)
  .then(weather => {
      document.getElementById('farenheit').text = weather.temperatureF;
  .catch(error => console.log(JSON.stringify(error)))


These are my personal picks of open-source modules for Fitbit, and I hope they accelerate your development efforts.

One thing I do want to note is that for every open-source module you use, there were many people behind the scenes spending the hours to build it. One of the harsh reality is open-source is unsustainable for the majority of authors, so if you can please sponsor, contribute, or donate to the authors.