Samsung Aggressively Speeds Up One UI 9 (Android 17) Development; Massive Influx of Galaxy A-Series Test Builds Spotted

Samsung’s One UI 9 development based on Android 17 is gathering pace rapidly. Following recent sightings of One UI 9 test builds for Galaxy S26, S25, S24, S23 series and foldables, the company has now expanded testing to several Galaxy A-series devices.

The latest server listings reveal fresh One UI 9 firmware for the Galaxy A17, Galaxy A55, Galaxy A16, Galaxy A07, and even the upcoming Galaxy A57, suggesting Samsung is significantly speeding up Android 17 development.

Galaxy A17 One UI 9 Build Appears on European Servers

Samsung has started testing One UI 9 for the Galaxy A17 in Europe.

Build Number:

• A175FXXU5DZF5
• A175FOXM5DZF5
• A175FXXU5DZF5

The appearance of this firmware confirms active Android 17 development for the Galaxy A17 and further expands Samsung’s growing One UI 9 testing program.

Galaxy A55 Receives First One UI 9 Test Build

The Galaxy A55 has now joined Samsung’s Android 17 testing program.

Build Number:

• A556BXXUFEZF7
• A556BOXMFEZF7
• A556BXXUFEZF7

The Galaxy A55 remains one of Samsung’s most important mid-range smartphones. Interestingly, the Galaxy A35 was also spotted in One UI 9 testing earlier, indicating Samsung is prioritizing its popular A-series lineup as development accelerates.

Galaxy A07 One UI 9 Testing Begins Across Asia

Samsung has also started testing Android 17 for the Galaxy A07 in Thailand, Vietnam, Malaysia, and the Philippines.

Build Number:

• A075FXXU5DZF7
• A075FOLM5DZF7
• A075FXXU5DZF5

There is still no sign of One UI 9 testing for the Galaxy A07 5G variant.

Galaxy A16 One UI 9 Development Gains Momentum

Samsung appears to be moving quickly with Galaxy A16 development.

A new One UI 9 test build has been detected for the Galaxy A16 LTE model.

Build Number:

• A165FXXUAEZF5
• A165FOXMAEZF5
• A165FXXUAEZF5

Galaxy A16 5G Gets New One UI 9 Build

Samsung has also pushed a newer Android 17 test build for the Galaxy A16 5G.

Firmware Version:

• A166BXXU8EZFD
• A166BOXM8EZFD
• A166BXXU8EZFD

The newer build suggests ongoing optimization and feature integration work.

Galaxy A57 Also Joins One UI 9 Testing

The upcoming Galaxy A57 has now been spotted running a fresh One UI 9 test firmware.

Build Number:

• A576BXXU3BZFB
• A576BOXM3BZFB
• A576BXXU3BZFB

Although Samsung has yet to officially announce the Galaxy A57, active Android 17 testing indicates the company is already preparing software support for its next-generation mid-range lineup.

One UI 9 Features Revealed So Far

While Samsung hasn’t officially unveiled One UI 9, several features have already surfaced through leaks and testing.

Early One UI 9 builds have also revealed visual refinements throughout the operating system. Samsung appears to be working on upgraded blur effects, smoother animations, enhanced transparency elements, and a more polished overall interface. The changes may not represent a dramatic redesign, but they could significantly improve the fluidity and premium feel of the user experience.

Reports suggest One UI 9 may bring Network Speed Indicator through Good Lock QuickStar, a new Location Privacy Indicator, enhanced blur effects and animations, and even a Block Internet feature for apps.

Samsung may also introduce new cross-device ecosystem features in One UI 9, further strengthening integration between Galaxy smartphones, tablets, wearables, and PCs.

Samsung Is Clearly Speeding Up One UI 9 Development

The growing number of firmware sightings suggests Samsung has entered a broader testing phase for One UI 9.

Recently spotted devices now include:

• Galaxy S26 Series
• Galaxy S25 Series
• Galaxy S24 Series
• Galaxy S23 Series
• Galaxy Z Fold Series
• Galaxy Z Flip Series
• Galaxy A57
• Galaxy A55
• Galaxy A35
• Galaxy A17
• Galaxy A16 LTE
• Galaxy A16 5G
• Galaxy A07

Notably, Samsung has already started the One UI 9 Beta Program for the Galaxy S26 series, while internal testing continues across older flagship and mid-range devices.

When Will Samsung Release One UI 9?

Samsung has not officially announced a stable rollout timeline for One UI 9. However, the increasing number of test builds appearing across Galaxy devices suggests Android 17 development is progressing rapidly.

Users wondering whether their Galaxy smartphone will receive the update can check our continuously updated One UI 9 eligible devices list.

For now, these latest Galaxy A-series firmware sightings provide the clearest indication, yet that Samsung is aggressively preparing One UI 9 for one of its widest device rollouts ever.

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