ASUS ROG Phone 9 vs Xiaomi 15 Ultra
The Verdict
Both flagships share identical processors and similar battery capacities, but diverge meaningfully in imaging and display technology. ASUS ROG Phone 9 targets gamers with its exceptional 185Hz LTPO AMOLED display and optimized cooling, while Xiaomi 15 Ultra prioritizes photography with a 1-inch main sensor, impressive 200MP periscope telephoto, and higher 3200x1440 resolution. Xiaomi's 90W wired plus 50W wireless charging significantly outpaces ASUS's 65W wired-only approach, and the titanium frame suggests better durability. Display brightness favors Xiaomi at 3200 nits versus 2500. However, ASUS's gaming-centric design with its 185Hz refresh rate and dedicated cooling may appeal more to mobile gamers. For multimedia creators and camera enthusiasts, Xiaomi 15 Ultra delivers superior zoom capabilities and overall photographic flexibility. At identical $999 pricing, Xiaomi offers more rounded flagship features, though ASUS excels specifically for gaming performance.
Who Should Buy
Buy the ASUS ROG Phone 9 if…
- →185Hz display refresh rate is the highest on any smartphone
- →Snapdragon 8 Elite with advanced cooling sustains peak gaming performance
- →5800 mAh battery handles extended gaming sessions
Buy the Xiaomi 15 Ultra if…
- →200MP periscope telephoto with 5x optical zoom rivals Galaxy S25 Ultra
- →1-inch main sensor with Leica optics produces stunning photos
- →Titanium frame gives a premium, durable build
Category Scores
Pros & Cons
ASUS ROG Phone 9
Pros
- 185Hz display refresh rate is the highest on any smartphone
- Snapdragon 8 Elite with advanced cooling sustains peak gaming performance
- 5800 mAh battery handles extended gaming sessions
- AniMe Vision LED dot-matrix display on the back for notifications
- AirTrigger ultrasonic shoulder buttons enhance mobile gaming controls
Cons
- Heavy at 227 g — feels chunky as a daily driver
- 65W charging is slow compared to Chinese gaming phone rivals
- Camera is competent but not flagship-level for the price
- Gaming-focused design is too aggressive for many users
Xiaomi 15 Ultra
Pros
- 200MP periscope telephoto with 5x optical zoom rivals Galaxy S25 Ultra
- 1-inch main sensor with Leica optics produces stunning photos
- Titanium frame gives a premium, durable build
- 4K@120fps video recording is industry-leading
- 90W fast charging and 50W wireless on a huge 5810 mAh battery
Cons
- Heavy at 229 g and thick at 9.17 mm
- Very expensive at $999 with limited global availability
- HyperOS software experience lags behind iOS and One UI
- Camera bump is extremely large
Full Specifications
| Spec | ASUS ROG Phone 9 | Xiaomi 15 Ultra |
|---|---|---|
| Software | Android 15 | Android 15 (HyperOS 2) |
| Body | ||
| Weight | 227 g | 229 g |
| Material | Aluminum frame, Gorilla Glass Victus 2 | Titanium frame, Gorilla Glass Victus 2 |
| IP rating | IP68 | IP68 |
| Dimensions | 163.8 x 77.0 x 8.9 mm | 161.1 x 75.2 x 9.17 mm |
| Camera | ||
| Main camera | 50 MP, f/1.9, OIS (Sony IMX906) | 50 MP, f/1.63, OIS (1-inch sensor) |
| Front camera | 32 MP, f/2.4 | 32 MP, f/2.0 |
| Video | 8K@24fps, 4K@60fps | 8K@30fps, 4K@120fps |
| Ultrawide | 13 MP, f/2.2, 120-degree | 50 MP, f/2.0, 128-degree |
| Telephoto | — | 200 MP, f/2.6, 5x periscope optical zoom, OIS |
| Memory | ||
| RAM | 16 GB | 16 GB |
| Storage options | 256 GB, 512 GB | 256 GB, 512 GB, 1 TB |
| Battery | ||
| Capacity | 5800 mAh | 5810 mAh |
| Charging | 65W wired | 90W wired |
| Wireless charging | — | 50W wireless |
| Display | ||
| Size | 6.78 inches | 6.73 inches |
| Type | LTPO AMOLED | LTPO AMOLED |
| Resolution | 2400 x 1080 | 3200 x 1440 |
| Refresh rate | 185Hz | 1-120Hz |
| Brightness (nits) | 2500 | 3200 |
| Processor | ||
| CPU | Octa-core (2x4.32 GHz + 6x3.53 GHz) | Octa-core (2x4.32 GHz + 6x3.53 GHz) |
| GPU | Adreno 830 | Adreno 830 |
| Chipset | Qualcomm Snapdragon 8 Elite | Qualcomm Snapdragon 8 Elite |
| Connectivity | ||
| 5G | ||
| NFC | ||
| USB | USB-C 3.2 | USB-C 3.2 |
| Wi-Fi | Wi-Fi 7 | Wi-Fi 7 |
| Bluetooth | 5.4 | 5.4 |
Related Comparisons
This comparison is based on verified manufacturer specifications covering display, performance, camera, battery, and build quality. Scores are generated by analyzing specs across weighted categories on a 10-point scale. Learn more about our methodology.
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