Ever since Android 12 came into existence, Samsung device owners have been anxiously awaiting their chance to get a taste of the revamped One UI. After the completion of the public beta program, we actually started to see the first official One UI 4 updates land on several Galaxy devices. The joy from this rollout didn’t last long though, as the release was temporarily halted due to numerous bugs. Existing beta participants then received another test build, on top of which Samsung prepared a revised stable update -- but that plan didn't work out. It took a bit of time to figure out what the root cause of the issue was, but at last, Samsung has started rolling out the update once again.

Samsung Android 12 Tracker: Here are all the official One UI 4.0 stable and beta builds to download and install

While Google works closely with various OEMs to help them deploy the latest version of Android as quickly as possible, there are bound to be some unique issues that pop up from time to time. Naturally, the more changes you make to the stock Android codebase, the more chances there are for bugs to surface from new updates.

These issues are exactly what Samsung initially experienced with its Android 12 rollout on the Galaxy S21 series, the Galaxy Z Flip 3, and the Galaxy Z Fold 3. In order to address the compatibility issues between the new update and the Google Play system, Samsung and Google collaborated to find the solution. Since the bug factor has been eliminated, the Galaxy S21 lineup and the current-gen Galaxy foldables are now receiving new One UI 4 stable updates across the globe.

Samsung Galaxy S21 One UI 4 BULC OTA
Screenshot credit: Samsung Community member satio

For the global variants of the Galaxy S21 family, the new release is tagged as G99xBXXS3BULC (G99xNKSS3BULC for the Korean models). On the other hand, the Galaxy Z Flip 3 and the Galaxy Z Fold 3 are now receiving new updates with the firmware version F711xxxS2BUL6 and F926xxxS1BUL6 respectively. The Android security patch level of these builds is December 2021.

XDA Forums: Galaxy S21 || Galaxy S21 Plus || Galaxy S21 Ultra || Galaxy Z Flip 3 || Galaxy Z Fold 3

In case you haven’t received the update prompt on your Galaxy S21, Galaxy Z Flip 3, or Galaxy Z Fold 3 yet, you can head over to the Software Update section in the Settings app to check if the new build is available for your unit. Alternatively, take the route of manual installation by following our tutorial on Samsung Galaxy firmware flashing.