Firmware changelog

Release notes for every firmware version. For reproducibility, record the version that ran during each deployment.

What “build” means. Each release below also lists a build number. That is the identifier a collar transmits with its data, and it is what the dashboard shows for a deployed device — so if a collar reports build 248, it is running v1.13.0. Cite the version; use the build to work out which version a collar in the field is on.