The Galaxy Watch 7 and the Galaxy Watch Ultra, which were launched last month, are the world's first smartwatches running Wear OS 5. Those watches and previous-generation Galaxy Watches could even get the One UI 6.5 Watch update in the future, as Google seems to be working on Wear OS 5.1, which is based on the latest version of Android.
Galaxy Watches could get One UI 6.5 Watch update based on Wear OS 5.1
According to a report from Android Authority, Google is working on Wear OS 5.1, which is based on Android 15. The One UI 6 Watch software is based on Wear OS 5, which is, in turn, based on Android 14.
Android for smartphones and tablets follows a yearly release cycle, which means we get a major new version every year. However, Wear OS doesn't follow the early cycle, and its release timeline is inconsistent. There was a Wear OS 3.5 update in 2022, but there was no Wear OS 4.5 update, and Google jumped straight to Wear OS 5.
With the rising sales of Wear OS smartwatches, Google might have decided to release a new version of Wear OS based on the latest version of Android every year. Since the company appears to be working on a new version of Wear OS (based on the latest Android version), it is possible that it will introduce more features, and those features could make it to Galaxy Watches in the coming months.
However, the development of Wear OS 5.5 seems to be in a pretty early stage, so it is possible that Google will release it as the Wear OS 6 update by the time it is done with all the development. If the new Wear OS version gets new system behavior, it has a chance of being named Wear OS 6, but if it only introduces new features and apps, it might be released as Wear OS 5.5.
Based on what Google does, Samsung will likely release the next version of One UI Watch. The Galaxy Watch 4 and the Galaxy Watch 4 Classic will get the One UI 6 Watch update, and when that happens, they will have received three major Wear OS updates. They might not get the next big Wear OS update. The Galaxy Watch 6 and the Galaxy Watch 7 series might get it, though.