Samsung Galaxy S21 series: Technical features at a glance

What is convincing and where are there weaknesses?

👍 Smooth 120 Hz displays: AMOLED screens will still be at the top level in 2025.

👍 Solid performance: The Exynos 2100 / Snapdragon 888 is sufficient for everyday tasks and gaming.

👍 Good camera equipment: The S21 Ultra is particularly impressive with its powerful zoom and high resolution.

👎 No expandable storage: The Galaxy S21 series does not offer a microSD slot.

👎 Battery life varies: The S21 Ultra lasts longer, but the S21 can fail faster with intensive use.

👎 update support ends: Android and One UI updates are only available until 2025, security updates until 2026.

Performance test: Can the Galaxy S21 still keep up?

The Galaxy S21 uses the Exynos 2100 in Germany, while the Snapdragon 888 is installed in North America. Both chips deliver solid performance, but show some differences. The tech YouTuber "Upwards." tested how the S21 will perform in 2025. Social media and simple multitasking run smoothly, but the device gets noticeably warm when switching apps frequently.When gaming, it handles "Genshin Impact" on medium settings with a stable 30 FPS, but higher graphics settings lead to heating problems. After prolonged use, slight stuttering can also occur.

Interesting: Geekbench has removed the Galaxy S21 from its benchmark lists because the device uses an artificial "benchmark mode" that does not reflect actual everyday performance. This means that official benchmark values ​​are less meaningful than real usage tests.

➡ In practice, the S21 remains fast enough for normal tasks, but could lag behind newer models when it comes to demanding gaming or intensive video editing.

📱 Upwards.: “The Galaxy S21 in 2025 – still a good choice?”

Tech YouTuber Upwards has once again subjected the Galaxy S21 to a detailed everyday test and came to a clear conclusion: solid for the price, but not without weaknesses.

✔ Good 120 Hz AMOLED display: Smooth scrolling and bold colors.

✔ Powerful Exynos 2100 / Snapdragon 888: Fast enough for everyday applications.

✔ Main camera impresses: Good colors and details, especially in daylight.

✔ price-performance ratio: Available cheaply second-hand, still a solid device.

❌ Battery life disappointing: Only around 4 hours of screen-on time, not suitable for power users.

❌ heat development during heavy use: The device can get warm, especially with an Exynos processor.

❌ Hybrid zoom instead of real optical zoom: The camera is versatile, but not at the top level.

➡ Conclusion of Upwards.: The Galaxy S21 remains a solid everyday device, but those who need more power and battery life should consider a newer model.

📱 Digital Slang: “S21 Ultra in 2025 – still a top flagship?”

YouTuber Digital Slang has tested the Galaxy S21 Ultra again after several years and comes to the conclusion: It remains one of the best used high-end smartphones.

✔ Brilliant 6.8-inch display: QHD+ with 120 Hz and high brightness.

✔ Fantastic camera setup: Real optical zoom (3x & 10x), strong main camera.

✔ Solid battery life: 5000 mAh lasts all day.

✔ premium features: S Pen support, IP68, wireless charging.

❌ Heavy and large: At 227g, not comfortable for everyone to use.

❌ Slow loading: 25W fast charging is no longer up to date.

❌ Aging processor: The Exynos 2100 / Snapdragon 888 is solid, but no longer cutting edge.

➡ Conclusion from Digital Slang: If you are looking for an affordable high-end smartphone with a top camera and premium features, the S21 Ultra 2025 is still a good choice.

Battery life: How long will the Galaxy S21 last?

At release, the models with Exynos processor offered the following runtimes according to The Tech Chap:

📌 Galaxy S21: 6 hours 59 minutes

📌 Galaxy S21+: 8 hours 36 minutes

📌 Galaxy S21 Ultra: 9 hours 4 minutes

Since batteries lose capacity over time, the values ​​in 2025 are likely to be somewhat lower. Heavy users in particular will notice that the running time is no longer achieved at the beginning. However, those who rely on long running times can have the battery replaced, which significantly extends the life of the device. The S21 Ultra remains the best choice here, while the S21 may be too small for intensive use.

Our conclusion: Should I still buy a Galaxy S21 in 2025?

The Galaxy S21 still offers solid performance for everyday use in 2025, especially as a cheap option on the used market. If you're looking for a compact device with a good camera, the S21 is a good choice, while the S21+ offers better battery life. The S21 Ultra remains the best choice for those who value a high-resolution display, true optical zoom, and longer battery life.

However, you have to expect a decrease in battery life and a lack of Android updates. If you want a more modern device with better battery life and the more efficient Snapdragon processor, you should get the Samsung Galaxy S23 series This continues to offer a strong price-performance ratio, combined with long-term update support and a more powerful chipset.