The site says it tracks 53 makers and more than 8,000 firmware versions, with recent listings for Blackmagic Camera, Nikon, Canon and Z CAM hardware. It does not rehost firmware; the download links go to the original vendor.
The attraction is the alert workflow. Search for a device you own, check its current version, and decide whether an email notification is more useful than occasionally searching support pages.
Before adding all your gear, test one camera or audio device and confirm the site correctly identifies the latest official release. Never install a firmware file from an unknown mirror.
What to do: Search one piece of camera or AV equipment on the tracker and compare its reported firmware against the manufacturer.