Samsung Kicks Off One UI 8.5 Testing on Galaxy S23 Ultra

It’s no secret that Samsung is developing the next big Android 16-based update, the One UI 8.5. The update will bring a ton of features along with visual improvements across the board. Now, its firmware build for the Galaxy S23 Ultra has come to light, suggesting that testing is already underway for the device.

One UI 8.5 internal development for the Galaxy S23 series begins

A few weeks ago, Samsung began pushing the One UI 8 update for the Galaxy S23 series in several regions. However, the company has now paused the rollout without sharing any reason. Rest assured, the rollout will hopefully resume soon.

Amidst this uncertainty, Samsung has kicked off internal development of One UI 8.5 for the Galaxy S23 series, as noted by tipster Tarun Vats. The build version is S918BXXU9FYJ3 (for Galaxy S23 Ultra). Note that the build is currently in the early testing phase, so more builds should surface in the coming weeks as development progresses. The tipster also said that the firmware has not yet appeared on the company’s test server.

Samsung may open the beta program for the upcoming One UI 8.5 by the end of November 2025. However, whether the Galaxy S23 series will be part of this program remains to be seen. The company usually prioritizes its latest premium devices, so the most plausible models include the Galaxy S25 series, and Galaxy Z Fold 7 and Z Flip 7. The upcoming Galaxy S26 series could mark the debut of the stable One UI 8.5.

Thanks to early leaks, we already have a fair idea of what Samsung is cooking up with One UI 8.5. One of the most notable additions is the AI Agents Integration, which will allow users to access multiple AI providers directly from a new launcher shortcut. These include Google’s Gemini, Gauss Cloud, and Perplexity. You can check out our One UI 8.5 coverage, where we have detailed all the latest features and enhancements revealed so far.