Samsung has now released One UI 5 Watch for the Galaxy Watch4 and Galaxy Watch4 Classic, following an equivalent release last week for the Galaxy Watch5 series.
Incidentally, it has since emerged that the Galaxy Watch5 and Galaxy Watch5 Pro support Google's long-awaited 'Watch Unlock' functionality, which may well be a Galaxy Watch and Pixel Watch exclusive like Google Assistant has proven to be.
Still, this should mean that the Galaxy Watch4 and Galaxy Watch4 Classic will be capable of unlocking a paired smartphone and a Chromebook eventually, too.
According to Samsung's changelogs, One UI 5 Watch arrives on the Galaxy Watch4 series as 'HWH3'.
For reference, the company delivered equivalent updates to the Galaxy Watch5 series as 'BWH3'.
As far we can tell, the Galaxy Watch4 and Galaxy Watch4 Classic have received the same changelog as their successors.
Thus, One UI 5 Watch brings backup and restore functionality to the Galaxy Watch4 series, as well as refined call controls. Additionally, a new Battery tile means that it is now possible to check the battery levels of all your devices directly on your Galaxy Watch4 or Galaxy Watch4 Classic.
Unfortunately, Samsung has also bundled the 2023-7-01 set of security patches, which are two months old at this point.
Please see Samsung's changelogs for more details.