As we informed you early this year, Google was open-sourcing the code for Pebble watches, making about 95% of the software available to the community. The last 5%—the mobile app—remained closed. That’s now changed with the announcement of Eric Migicovsky, the founder of Pebble and the person leading its 2025 relaunch under his new company, Core Devices.

As of this week, the entire software stack behind modern Pebble watches, including PebbleOS, the mobile companion app, developer tools, and the Pebble Appstore backend, is now fully open source.

The new open-source mobile app is central to that change. When the original company shut down, Pebble users faced a significant problem: without a companion app, the watches were effectively unusable.