The Galaxy Z Fold 8 and Galaxy Z Fold 8 Ultra, the first Samsung devices to run One UI 9.0 out of the box, will hit retail shelves soon. Meanwhile, what appears to be the first One UI 9.5 firmware has surfaced on the company’s servers.The firmware (build number S958USQU0AZH3) was spotted for the US variant of the Galaxy S27 Ultra. The Galaxy S27 series will debut with One UI 9.5, just as the Galaxy S26 series launched with One UI 8.5.Development of One UI 9.5 is believed to have begun as early as May this year, but this is the first actual firmware build we have seen on Samsung’s servers.One UI 9.5 development progressing on scheduleThe first One UI 8.5 build for the Galaxy S26 series was spotted on July 25 last year, so development of the next One UI version appears to be progressing on the usual schedule.That schedule itself was accelerated last year with One UI 8 and One UI 8.5. Samsung began releasing major One UI updates earlier to match Google’s faster Android release cycle starting with Android 17.That doesn’t mean One UI 9.5 will be available for public beta testing anytime soon. Samsung has yet to release the stable One UI 9.0 update for any devices older than the Galaxy Z Fold 8 and Flip 8. Even the One UI 9 beta program is currently open only to the Galaxy S26 series.Samsung launched the One UI 8.5 beta program in December last year, and we can expect the One UI 9.5 beta to begin around the same time this year before the stable version officially debuts with the Galaxy S27 series in 2027.