Considering an older smartphone in 2025 can be a smart move, especially as new models quickly drop in price. But, it also means navigating a market full of devices that might be past their prime. You might have come across the Samsung Galaxy S21 and the Samsung Galaxy A21 in your search. While both are part of the extensive Samsung Galaxy series, these two phones were miles apart when they were first released. This guide will dive deep into the Samsung S21 vs A21, exploring their differences in performance, cameras, and, most importantly, their relevance and value in today’s used market. By the end, you’ll know exactly which (if either) is right for you.
Key Takeaways: S21 vs. A21 at a Glance
Looking for a quick rundown? This table summarizes the main points of comparison between these two older Android phones. It helps you quickly see where each excels or falls short in 2025.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Original Positioning | Flagship (Premium) | Budget (Entry-Level) |
| Performance (CPU/RAM) | Much Stronger (Snapdragon 888/Exynos 2100, 8GB RAM) | Basic (MediaTek Helio P35, 3-4GB RAM) |
| Display Quality | Excellent AMOLED display (120Hz, high resolution) | Basic LCD display (60Hz, lower resolution) |
| Camera Quality | Very Good (Versatile, great low light) | Decent for basics (Struggles in low light) |
| Software Support (2025) | Likely no major Android OS updates, limited security patches. | No major OS or security patches; high security risks. |
| Connectivity | 5G connectivity, Wi-Fi 6 | 4G LTE only, older Wi-Fi |
| Durability | IP rating for water/dust, Gorilla Glass Victus | Basic plastic build, no IP rating |
| Price (Used/Refurbished 2025) | Higher ($150-$250 USD) | Very Low ($50-$100 USD) |
| Best For | Performance, camera, screen if software isn’t a top priority. | Absolute budget, secondary phone, very light use; not recommended due to security. |
Original Goal: Flagship vs. Budget
When these phones first hit the market, they were aimed at completely different audiences. The Samsung Galaxy S21, released in early 2021, was a full-blown flagship phone. It packed all the latest tech and features, designed to compete with the very best smartphones available. In contrast, the Samsung Galaxy A21, which came out in mid-2020, was squarely in the budget smartphone category. It was built for everyday essentials, offering basic functionality at a much more affordable price point. This fundamental difference in original intent truly defines how they have aged.
Performance: Speed, Multitasking, and Gaming
This is where you’ll see one of the biggest gaps between the two phones, especially in 2025. The Samsung Galaxy S21 featured top-tier processors for its time, either the Qualcomm Snapdragon 888 or Samsung’s Exynos 2100, depending on your region. Paired with 8GB of RAM, this phone was a powerhouse. Even now, those specifications mean the S21 can handle most tasks you throw at it. From demanding apps to graphic-intensive gaming, it will still feel snappy and responsive. If you’re wondering if the Samsung S21 is still good in 2025 for performance, the answer is a resounding yes, purely from a hardware standpoint. The Samsung Galaxy A21, but, was equipped with a more modest MediaTek Helio P35 CPU and typically came with 3GB or 4GB of RAM. This was fine for basic tasks back then, but in 2025, it will really show its age. You’ll likely experience noticeable lag even with simple apps. For anything beyond light social media browsing and messaging, the A21 will struggle significantly. Multitasking will be a pain, and serious mobile gaming is generally out of the question.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Processor | Snapdragon 888 / Exynos 2100 | MediaTek Helio P35 |
| RAM | 8GB | 3GB or 4GB |
| Performance in 2025 | Still very capable for most tasks, including demanding apps and games. | Struggles with anything beyond basic tasks; noticeable lag. |
| 5G Support | Yes | No (4G LTE only) |
Display Quality: Visual Experience Compared
The screen is another area where the Samsung Galaxy S21 truly shines compared to its budget counterpart. It boasts a stunning Dynamic AMOLED display with a 120Hz refresh rate. This means colors are vibrant, blacks are deep, and scrolling feels incredibly smooth. Watching videos, browsing photos, or just navigating the interface on the S21 is a really pleasant experience, even by today’s standards. The resolution is also higher, making everything look crisp and detailed. The Samsung Galaxy A21 comes with a standard LCD display, typically refreshing at 60Hz. While it’s perfectly functional for basic use, you’ll notice a significant difference in color vibrancy, contrast, and overall smoothness. It’s perfectly adequate for reading messages and browsing, but it won’t offer the same immersive viewing experience.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Panel Type | Dynamic AMOLED 2X | TFT LCD |
| Refresh Rate | 120Hz | 60Hz |
| Size | 6.2 inches | 6.5 inches |
| Resolution | 2400 x 1080 pixels (FHD+) | 1600 x 720 pixels (HD+) |
| Peak Brightness | Up to 1300 nits | Around 400 nits |
Camera Capabilities: Capturing Memories in 2025
If mobile photography is important to you, the Samsung S21 vs A21 camera comparison is pretty straightforward. The S21 features a versatile triple-camera setup on the back: a 12MP main sensor, a 12MP ultrawide, and a 64MP telephoto lens with 3x hybrid optical zoom. This setup means you get excellent photo quality in good lighting, good performance in low light, and the flexibility of different lenses. The video recording capabilities are also far superior on the S21, offering up to 8K resolution. It’s still a very capable smartphone camera in 2025. The Samsung Galaxy A21 has a quad-camera system with a 48MP main camera, an 8MP ultrawide, a 2MP macro, and a 2MP depth sensor. While it has more lenses on paper, the overall quality isn’t comparable to the S21. It can take decent photos in bright daylight, but struggles significantly in challenging conditions or low light. For quick snapshots or sharing on social media without much fuss, the A21 might be okay. But, don’t expect the detail, dynamic range, or low-light performance you’d get from the S21.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Main Camera | 12MP (f/1.8, OIS) | 48MP (f/2.0) |
| Ultrawide | 12MP (f/2.2) | 8MP (f/2.2) |
| Telephoto / Macro | 64MP Telephoto (3x hybrid zoom) | 2MP Macro, 2MP Depth |
| Front Camera | 10MP (f/2.2) | 13MP (f/2.2) |
| Video | Up to 8K@24fps, 4K@60fps | 1080p@30fps |
| Overall Quality (2025) | Very good, versatile, good low light. | Basic, okay in good light, struggles otherwise. |
Battery Life & Charging: Powering Through Your Day
The Samsung Galaxy S21 has a 4,000mAh battery, while the Samsung Galaxy A21 also comes with a 4,000mAh unit. On paper, they might seem similar, but real-world endurance can differ significantly due to processor efficiency and screen technology. The S21 generally offered decent battery life, typically lasting a full day for most users when new. It also supports 25W fast charging and wireless charging, which is a convenient feature. The A21, despite having the same battery capacity, might offer slightly longer endurance for light users due to its less demanding screen and processor. But, it only supports 15W charging and lacks wireless charging. When considering S21 vs A21 battery life in 2025, remember that any used phone’s battery will likely have some degradation, impacting its original capacity.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Battery Capacity | 4,000 mAh | 4,000 mAh |
| Charging Speed | 25W wired, 15W wireless | 15W wired |
| Wireless Charging | Yes | No |
| Expected Battery Life (Used 2025) | Decent, but expect some degradation; probably half a day to full day. | Good for light use, but degradation common; likely full day for light use. |
Design, Build, and Durability
The Samsung Galaxy S21 has a more premium feel, featuring a “Glasstic” (matte plastic) back, a metal frame, and Gorilla Glass Victus on the front for better scratch resistance. It also boasts an IP rating for water and dust resistance, meaning it can survive accidental splashes or even submersion. The overall phone design is sleek and modern, and it feels pretty solid in hand. This premium build quality means it generally holds up better over time, assuming it hasn’t been abused. The Samsung Galaxy A21 has a more utilitarian phone design, with an all-plastic build quality. While plastic can be more forgiving if dropped, it lacks the premium feel and scratch resistance of the S21. There’s no official IP rating for water or dust resistance either, so you’d need to be more careful with it.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Back Material | Glasstic (Polycarbonate) | Plastic |
| Frame Material | Aluminum | Plastic |
| Front Glass | Gorilla Glass Victus | Standard Glass |
| IP Rating | IP68 (Water and dust resistant) | None |
| Dimensions/Weight | Compact, lighter (151.7 x 71.2 x 7.9mm, 169g) | Slightly larger, similar weight (163.7 x 75.3 x 8.9mm, 193g) |
Software Experience & Updates (Crucial for 2025)
This is arguably the most critical factor when buying an older phone in 2025. The Samsung Galaxy S21 launched with Android 11 and Samsung’s One UI 3.1. It received three major Android OS updates, officially stopping at Android 14 and One UI 6. It might still get some infrequent security patches into early 2025, but it will not receive Android 15 or One UI 7. This means you’ll be running on somewhat outdated software, which could become a minor security risk over time as new vulnerabilities are discovered and not patched. The Samsung Galaxy A21 shipped with Android 10 and One UI 2.0. It received fewer major updates, typically stopping around Android 12. This means it’s now running a very old version of Android and has received no security patches for a long time. Using an outdated Android phone like the A21 in 2025 comes with significant security risks. Your data could be more vulnerable to exploits, and some newer apps might not function correctly or at all. For these reasons, it’s generally not recommended for any primary use involving sensitive data.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Original Android Version | Android 11 (One UI 3.1) | Android 10 (One UI 2.0) |
| Latest Major OS Update (End-of-Life) | Android 14 (One UI 6) | Android 12 (One UI 4.1) |
| Security Updates in 2025 | Very limited, possibly none by late 2025. | None, significant security risks. |
| Experience in 2025 | Functionally fine, but no new features or critical security patches. | Very outdated, potential app compatibility issues, high security risk. |
Connectivity & Unique Features
Connectivity is another area where the S21 still holds up pretty well. It supports 5G connectivity, Wi-Fi 6, Bluetooth 5.0, and NFC for contactless payments. This means it’s ready for current and near-future network speeds and common accessories. The Samsung Galaxy A21 is limited to 4G LTE, Wi-Fi 5, and Bluetooth 5.0. It does have a couple of features the S21 lacks: a 3.5mm headphone jack and a dedicated microSD card slot for expandable storage. The S21 only uses USB-C for headphones and doesn’t have a card slot. If you really value having a traditional headphone jack or needing to expand storage cheaply, the A21 does offer that. But, the S21’s overall modern connectivity, including 5G, generally outweighs these older features for most people in 2025.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| Cellular Network | 5G, 4G LTE | 4G LTE only |
| Wi-Fi | Wi-Fi 6 (ax) | Wi-Fi 5 (ac) |
| Bluetooth | Bluetooth 5.0 | Bluetooth 5.0 |
| NFC | Yes | Yes |
| USB Port | USB-C | USB-C |
| Headphone Jack | No | Yes (3.5mm) |
| Expandable Storage | No | Yes (microSD card slot) |
Current Market Value & Availability (December 2025)
By December 2025, finding new units of either the S21 or A21 will be extremely rare, if not impossible. Both phones are firmly in the used phone market and refurbished market. The prices have dropped considerably since their release. The Samsung S21 price in 2025 for a refurbished model in good condition typically ranges from about $150 to $250 USD. You might find it on platforms like Back Market or Swappa. The price will depend heavily on the condition, storage size, and the seller. The Samsung A21 price in 2025 is significantly lower, often between $50 and $100 USD for a used unit. Again, condition and seller matter a lot. These phones are readily available on various online marketplaces.
| Feature | Samsung Galaxy S21 | Samsung Galaxy A21 |
|---|---|---|
| New Availability (2025) | Extremely Rare/None | Extremely Rare/None |
| Refurbished Price (USD, approx.) | $150 – $250 | $50 – $100 |
| Where to Buy | Back Market, Swappa, eBay, local refurbishers. | eBay, local classifieds, budget online retailers. |
| Value for Money (2025) | Good if performance/camera are priorities and you accept software limitations. | Poor, largely due to critical software and security issues. |
Who Should Buy Which Phone in 2025?
If you’re on a tight budget but still want decent phone performance, a good camera, and a vibrant screen, the Samsung Galaxy S21 could still be a viable option. It’s a great choice for someone who needs a capable daily driver and understands the limitations of older software updates. It’s especially good if you’re not overly concerned about being on the absolute latest Android version, but you still want a premium feel. The S21 might also work well as a dedicated media consumption device or a secondary phone for specific tasks. For example, if you need a strong camera without breaking the bank, a refurbished S21 could fit the bill. Honestly, it’s difficult to recommend the Samsung Galaxy A21 for most people in 2025. Its lack of modern software support and security updates makes it a risky choice for a primary phone. If you literally need the cheapest possible device for emergency calls and very basic messaging, and security isn’t a concern, then maybe. It could serve as a very basic burner phone or a simple device for a young child who doesn’t access sensitive information. But, even for a child, the security aspects are a significant concern.
Common Pitfalls of Buying Older Smartphones
Buying a used or older smartphone, while budget-friendly, comes with its own set of potential issues. The most common one is battery degradation. A phone that’s several years old will likely have a battery that doesn’t hold a charge as well as it once did. You might find yourself needing to recharge much more frequently. Another major concern, as we’ve discussed, is the lack of software updates. This doesn’t just mean missing out on new features; it also means fewer or no security patches. This can leave your device vulnerable to new threats and exploits, which is a serious consideration for your personal data. Finally, older phones might also have general wear and tear. This could include cosmetic damage, screen burn-in (especially on AMOLED panels), or ports that are less reliable. Always buy from reputable sellers if possible, and carefully check return policies to protect your purchase.
FAQ: Your Top Questions Answered
Is Samsung S21 still good in 2025 for gaming?
Yes, the Samsung Galaxy S21 is still pretty good for gaming in 2025. Its powerful processor and ample RAM mean it can handle most modern mobile games with decent frame rates. But, you might need to lower graphics settings for the most demanding titles.
Is Samsung A21 worth buying in 2025?
Generally, no, the Samsung Galaxy A21 is not worth buying in 2025 for most users. Its severely outdated software and complete lack of security updates make it a significant security risk. Also, its performance is very slow by current standards.
What’s the difference between Samsung A21 and S21’s screen?
The main difference between the Samsung A21 and S21’s screen is that the S21 has a vibrant 120Hz AMOLED display, offering smoother visuals and better colors. The A21 uses a basic 60Hz LCD panel, which is less vibrant and not as smooth.
Will the S21 get Android 15 or One UI 7?
No, the Samsung Galaxy S21 will not receive Android 15 or One UI 7. Its official software update cycle ended with Android 14 and One UI 6.
Final Verdict: Making Your 2025 Decision
When it comes to the Samsung S21 vs A21 in 2025, the choice is pretty clear for most people. The Samsung Galaxy S21 still offers a surprisingly powerful experience, with a great screen, capable cameras, and snappy performance for its price on the refurbished market. Its biggest downside is the end of major software updates, which means accepting some long-term security considerations. The Samsung Galaxy A21, but, is a much tougher sell. While incredibly cheap, its outdated software poses a significant security risk, and its performance is simply too slow for most modern use. If you’re looking for a truly budget phone, it’s often better to save a bit more for a newer, entry-level device that still receives security patches. So, if you absolutely need a cheap phone and prioritize performance and camera, and can live with older software, a refurbished Samsung Galaxy S21 might be a decent pick for a secondary device or an enthusiast. But for most everyday users looking for a main phone, especially if you care about security, it’s probably best to steer clear of the A21 and perhaps even think twice about the S21 as a primary driver due to those lingering security concerns.
Sources & References
- Samsung S21 vs A21: Is the S21 really worth the extra cash?
- Samsung Galaxy S21 – Wikipedia
