Samsung Galaxy S21 Review – Is It the Best 5G Smartphone in 2025?

Introduction to Samsung Galaxy S21

The Samsung Galaxy S21 launched in early 2021 as a premium flagship smartphone, quickly gaining attention for its Samsung Exynos 2100 and Snapdragon 888 processor options, offering excellent 5G smartphone performance.

Its sleek design, reinforced with Gorilla Glass Victus durability, ensures both elegance and sturdiness, appealing to tech enthusiasts who value build quality. With a QHD+ AMOLED display and a 120Hz refresh rate, the device delivers a vibrant and smooth visual experience. Even in 2025, the S21 remains relevant as a mid-range 5G phone value, especially for those considering refurbished Samsung Galaxy or used Galaxy S21 Ultra devices, balancing performance, style, and affordability effectively.

Design and Build Quality

The Samsung Galaxy S21 Ultra specifications include a robust aluminum frame and a Gorilla Glass Victus durability back panel, giving it a premium flagship smartphone feel. The device measures 165.1 x 75.6 x 8.9 mm and weighs 228 grams. Despite its size, the smartphone ergonomics make it comfortable to hold, and the design still feels elegant in 2025.

However, some users find the large camera module slightly cumbersome on flat surfaces. The smooth matte finish ages gracefully but requires careful handling without a case. Overall, the tech innovation legacy and premium phone design maintain its appeal for those valuing build quality over modern compact trends.

Display and Visual Experience

The QHD+ AMOLED display of the Galaxy S21 offers vibrant colors and sharp images, with a 120Hz refresh rate that ensures smooth scrolling and responsiveness. The display brightness peaks at 1500 nits, providing excellent visibility in outdoor conditions, even under bright sunlight.

While newer models in 2025 may offer higher-resolution displays and improved efficiency, the S21 still provides a satisfying viewing experience. Its combination of high-resolution display and color accuracy remains a strong feature, particularly for streaming, gaming, and media consumption.

Performance and 5G Speed

Equipped with Samsung Exynos 2100 or Snapdragon 888 processor, the Galaxy S21 provides solid real-world performance for browsing, streaming, and casual gaming. Its multi-tasking performance handles everyday apps efficiently, though heavy multitasking can highlight performance limitations compared to newer devices.

The device supports advanced 5G connectivity, ensuring high-speed internet access. Streaming, downloads, and video calls work smoothly, showing the S21’s lasting 5G smartphone performance. Even in 2025, this phone can compete with mid-range 5G phones, especially when purchased refurbished.

Camera Capabilities

The Galaxy S21’s triple-camera setup includes a 108MP main camera and a periscope zoom lens, providing impressive mobile photography trends. Night mode photography is effective, and AI-assisted processing helps capture vibrant images even in low light.

Although camera image processing may not match the latest models’ speed, the S21’s mobile camera innovation continues to impress. Users benefit from advanced optical zoom and versatile shooting modes, making it suitable for photography enthusiasts and social media content creators.

Battery Life and Charging

The 4000mAh (or 5000mAh in Ultra models) battery offers decent endurance for daily use. Standard fast charging and wireless charging features ensure convenient power-ups. However, after four years, battery health check is recommended, and some users may consider smartphone battery replacement to maintain performance.

Battery longevity is critical for technology longevity and mobile device maintenance. Efficient power management and display optimization can help extend daily usage, even as the device ages.

Software and User Experience

The Galaxy S21 runs One UI 3.1 features on Android 11, upgradable to Android 13. Software security patches and updates help maintain safety, but updates may be limited in 2025. The device provides smooth navigation, customizable options, and cutting-edge smartphone features like Samsung DeX and Edge Panels.

Overall, the software experience contributes to the phone’s smartphone value proposition, offering intuitive usability and support for both casual and advanced users. Users should note potential limitations in mobile software updates for long-term security.

Comparison With Other 5G Smartphones

Compared to iPhone 14, Galaxy S22, and Pixel 7, the S21 still holds its ground with a competitive high-resolution display and mobile camera innovation. However, newer devices may outperform it in real-world performance and battery efficiency.

For those seeking refurbished Samsung Galaxy options, the S21 offers a balance of smartphone longevity, premium flagship smartphone design, and affordability. Its smartphone value proposition remains strong for users prioritizing design, camera, and 5G features over cutting-edge specs.

Price and Value Proposition in 2025

The S21, when purchased as a used Galaxy S21 Ultra or refurbished unit, is cost-effective compared to newer flagships. Its features, including the QHD+ AMOLED display, periscope zoom lens, and 5000mAh battery, provide mid-range 5G phone value at a fraction of the original price.

Table: Price Comparison (2025)

Conclusion – Is Samsung Galaxy S21 Still Worth It?

The Samsung Galaxy S21 offers a unique blend of tech innovation legacy, premium phone design, and 5G smartphone performance. For users seeking a refurbished phone marketplaces option, it delivers strong value and long-term usability.

While it cannot match the latest devices in processing speed or display innovation, the S21 remains a premium flagship smartphone alternative. Its combination of camera quality, display, software experience, and affordability makes it a wise choice for budget-conscious buyers in 2025. Consumer buying guide suggests checking battery health and device compatibility before purchase to ensure a smooth experience.

FAQs

1. Is the S21 waterproof?
The Samsung Galaxy S21 has an IP68 rating, making it waterproof up to 1.5 meters for 30 minutes.

2. What Android is the Galaxy S21?
The Galaxy S21 launched with Android 11 and One UI 3.1 features, upgradeable to Android 13.

3. How to know S21 original?
Check the IMEI number, official Samsung box, and device compatibility with carriers to verify authenticity.

4. What is the common issue in Samsung S21?
Common issues include battery drain, overheating, and occasional camera image processing delays.

5. What is the latest update for the S21?
The latest update is Android 13 with One UI 5.1 features for enhanced performance and security.

6. What is the biggest problem with Samsung phones?
Older models may face performance limitations after several software updates.

7. How to check Samsung battery health?
Go to Settings > Device Care > Battery to see the battery health check status.

8. How to identify a fake Samsung phone?
Verify the IMEI number, inspect the software, and check the premium phone design details.

9. How to check if a phone is new or used?
Inspect screen brightness, packaging, and look for scratches or signs of previous use.

10. How big is a S21 screen?
The standard S21 has a 6.2-inch display, while the S21 Ultra offers 6.8 inches diagonally.

11. What is the latest Android version for Samsung S21?
The latest version is Android 13 with One UI 5.1 features.

12. How long does the S21 Ultra battery last?
It lasts up to a full day depending on usage and streaming and casual gaming.

13. Which Samsung is waterproof?
Models like S21, S21+, and S21 Ultra with IP68 rating are waterproof.

14. Can S21 take pics underwater?
Yes, briefly, due to IP68 certification, but long-term underwater use is not recommended.

15. Is the Samsung S21 overheating?
It can overheat during heavy multi-tasking performance or extended gaming in high temperatures.