Galaxy S21 FE 5G Vs Galaxy S25 Ultra

The Samsung Galaxy S21 FE 5G, released in January 2022, and the Samsung Galaxy S25 Ultra, launched in February 2025, represent different tiers and generations within Samsung's smartphone lineup. While both operate on the Android platform with Samsung's One UI, the S25 Ultra, as a flagship model, introduces significant advancements in processing power, camera technology, and display quality compared to the more accessible S21 FE.

The lifespan of a smartphone is influenced by its release timeline, software support, and physical durability. These two devices offer different expectations in these areas.

• Release Timeline: The Galaxy S21 FE 5G was released in January 2022, making it over three years old at the time of the S25 Ultra's launch in February 2025. This age difference directly impacts their remaining support windows.
• OS Support Duration: The Galaxy S21 FE 5G launched with Android 12 and is expected to receive up to four major OS upgrades, concluding with Android 16. Its security updates transitioned to a quarterly schedule in October 2025. In contrast, the Galaxy S25 Ultra, launching with Android 15, is promised seven years of both OS and security updates, extending its support well into 2032.
• Repairability: The Galaxy S21 FE 5G received a repairability score of 7.5 out of 10, indicating a relatively straightforward repair process for many components, though its battery is glued in place. The Galaxy S25 Ultra, while scoring a provisional 5 out of 10, marks a significant improvement for a Samsung flagship, featuring easier battery replacement with pull tabs and modular camera components. However, display removal still requires adhesive, and official repair guides and parts availability can be challenging.

Performance differences between these two models are substantial, reflecting the generational gap and their respective market positions.

• Processing Power: The Galaxy S21 FE 5G is powered by a processor from 2021 (Snapdragon 888 or Exynos 2100), which provides snappy performance for everyday tasks and handles demanding applications well. The Galaxy S25 Ultra features a much newer, custom-tuned Snapdragon 8 Elite processor, offering significantly faster CPU and GPU speeds. This allows for exceptionally smooth multitasking, rapid app loading, and a superior experience with graphically intensive games and advanced AI features.
• Multitasking and Responsiveness: With 6GB or 8GB of RAM, the S21 FE 5G manages multiple applications effectively. The S25 Ultra, typically equipped with 12GB or 16GB of RAM, provides greater headroom for extensive multitasking and ensures sustained responsiveness even under heavy workloads.
• Battery Behavior: The S21 FE 5G has a 4500 mAh battery, with some users reporting it can last a full day or even a day and a half with moderate use, though heavy usage can lead to more frequent charging. The S25 Ultra houses a larger 5000 mAh battery, generally offering long battery life that can extend beyond a full day for many users. However, intensive tasks like prolonged camera use or gaming can deplete it more quickly than some rivals.

The visual experience is a key differentiator, with the S25 Ultra offering a more advanced display.

• Display Technology and Size: The Galaxy S21 FE 5G features a 6.4-inch Dynamic AMOLED 2X display with a resolution of 1080 x 2400 pixels. The Galaxy S25 Ultra boasts a larger 6.9-inch Dynamic LTPO AMOLED 2X display with a higher 1440 x 3120 pixel resolution, providing a more expansive and detailed viewing area.
• Refresh Rate and Brightness: Both devices offer a 120Hz refresh rate for smooth scrolling and animations. However, the S21 FE 5G's refresh rate is not adaptive, meaning it consistently runs at 120Hz or 60Hz. The S25 Ultra features an adaptive LTPO panel that can dynamically adjust its refresh rate from 1Hz to 120Hz, optimizing power consumption. The S25 Ultra also achieves higher peak brightness levels and includes Gorilla Glass Armor 2 with an anti-reflective coating, significantly improving outdoor visibility and reducing glare.
• Clarity and Protection: The S21 FE 5G's display is protected by Corning Gorilla Glass Victus. The S25 Ultra benefits from the newer Gorilla Glass Armor 2, offering enhanced durability against drops and scratches.

Camera capabilities show a clear progression, with the S25 Ultra offering a more versatile and high-resolution system.

• Rear Camera System: The Galaxy S21 FE 5G features a triple-camera setup: a 12 MP wide lens with OIS, an 8 MP telephoto lens with 3x optical zoom and OIS, and a 12 MP ultrawide lens. The Galaxy S25 Ultra elevates this with a quad-camera system, including a 200 MP primary sensor with OIS, a 50 MP ultrawide, a 50 MP telephoto with 5x optical zoom, and a 10 MP telephoto with 3x optical zoom.
• Photography Performance: The S21 FE 5G produces detailed and vibrant photos in good lighting, with its main and ultrawide lenses performing well. The telephoto lens is functional but can be less reliable in low-light conditions. The S25 Ultra offers consistently reliable image quality across its zoom range, with its improved 50 MP ultrawide camera delivering better low-light performance and crisper details.
• Video and Front Camera: Both devices support 4K video recording at 60fps, though the S21 FE 5G's Super Steady stabilization is limited to 1080p at 30fps. For selfies, the S21 FE 5G has a 32 MP front camera, while the S25 Ultra features a 12 MP front camera.