Asus Zenfone 9 vs Galaxy S23 Ultra

The Asus Zenfone 9, released in July 2022, and the Samsung Galaxy S23 Ultra, launched in February 2023, represent distinct approaches to the premium Android smartphone market. While both devices offer high-end performance, they cater to different user preferences regarding size, camera capabilities, and overall feature sets. Both operate on the Android platform, providing a familiar software experience with their respective custom interfaces.

The longevity of a smartphone is influenced by its release timeline, software support, and physical durability.

• Release Timeline and Software Support: The Asus Zenfone 9, released in September 2022, shipped with Android 12 and is upgradable to Android 13 and 14. User reports suggest that Asus typically provides a more limited period of guaranteed OS updates, potentially around two years. In contrast, the Samsung Galaxy S23 Ultra, released in February 2023, launched with Android 13 and has a commitment from Samsung for four generations of OS upgrades and five years of security updates, extending support until at least 2028. As of October 2025, the S23 series is running Android 16.
• Physical Durability: Both devices feature an IP68 rating for dust and water resistance, meaning they can withstand submersion in up to 1.5 meters of water for 30 minutes. The Zenfone 9 uses Corning Gorilla Glass Victus on its front display, while the Galaxy S23 Ultra incorporates the newer Gorilla Glass Victus 2 on both its front and back, offering enhanced scratch resistance.
• Repairability: The Zenfone 9 received a repairability score of 4.5 out of 10 in some assessments, with the screen noted as a challenging component to replace. The Galaxy S23 Ultra's repairability has varied in assessments; some sources gave it a 4 out of 10, while others noted improvements making it easier to repair, particularly the battery, with one assessment giving it a 9 out of 10.

Performance is a key aspect for daily usage, affecting everything from app responsiveness to demanding tasks like gaming.

• Processing Power: The Asus Zenfone 9 is equipped with a powerful processor from its generation, enabling it to handle demanding applications and multitasking smoothly. Users generally report excellent performance, describing the device as smooth and snappy. The Galaxy S23 Ultra features a newer generation processor, specifically optimized for Galaxy devices, which provides robust performance for intensive tasks and gaming.
• Storage and RAM: The Zenfone 9 offers configurations with 8GB or 16GB of RAM and 128GB or 256GB of internal storage, utilizing UFS 3.1 technology. The Galaxy S23 Ultra comes with 8GB or 12GB of RAM and storage options of 256GB, 512GB, or 1TB. Notably, versions with 256GB and higher storage use the faster UFS 4.0 standard, while 128GB versions use UFS 3.1.
• Battery Behavior: The Zenfone 9, despite its smaller size, is noted for its impressive battery life, often lasting a full day even with heavy use. The Galaxy S23 Ultra, with its larger battery capacity, also provides extended usage, with users reporting it can last through a full day.

The display is the primary interface for interaction, and its quality significantly impacts the user experience.

• Display Technology and Resolution: The Asus Zenfone 9 features a 5.9-inch AMOLED display with a 2400x1080 pixel resolution, resulting in a pixel density of approximately 445 pixels per inch (ppi). The Samsung Galaxy S23 Ultra boasts a larger 6.8-inch Dynamic AMOLED 2X display with a higher 3088x1440 pixel resolution, offering a sharper image with around 500 ppi.
• Brightness and Refresh Rate: The Zenfone 9's display supports a 120Hz refresh rate and can reach a peak brightness of 1100 nits. Some users have noted that the automatic brightness can be inconsistent, and manual brightness might not reach the full potential of the display. The Galaxy S23 Ultra features an adaptive 120Hz refresh rate (ranging from 1Hz to 120Hz) and a peak brightness of 1750 nits, providing excellent visibility even in bright outdoor conditions.
• Viewing Experience: The Zenfone 9 offers a vibrant and clear viewing experience on its compact screen. The Galaxy S23 Ultra's larger display and higher resolution contribute to an immersive viewing experience, with vibrant colors and deep blacks.

Camera systems are a significant consideration for many users, impacting photography and videography capabilities.

• Rear Camera System: The Asus Zenfone 9 includes a dual-camera setup with a 50MP main sensor featuring gimbal optical image stabilization (OIS) and a 12MP ultrawide sensor. The Galaxy S23 Ultra features a more comprehensive quad-camera system, including a 200MP main sensor with OIS, a 12MP ultrawide, and two 10MP telephoto lenses offering 3x and 10x optical zoom with OIS.
• Photography Performance: The Zenfone 9's main camera, with its gimbal stabilization, captures good quality photos, especially in well-lit conditions, and excels in video stabilization. However, some users report that its image processing can be inconsistent, sometimes over-sharpening or struggling with moving subjects and low-light conditions, particularly with the ultrawide lens. The Galaxy S23 Ultra is praised for its detailed and vibrant photos, improved low-light performance, and versatile zoom capabilities, allowing for clear images even at high magnifications.
• Video Recording and Audio: Both devices offer high-quality video recording. The Zenfone 9 can record up to 8K at 24fps and 4K at 30/60/120fps. The Galaxy S23 Ultra supports 8K video recording at 30fps and 4K at 30/60fps, with enhanced stabilization and wider angles for 8K footage. The S23 Ultra also offers 360-degree audio recording when paired with compatible earbuds. Both phones feature stereo speakers, and the Zenfone 9 uniquely retains a 3.5mm headphone jack.