Galaxy S21 5G Vs Galaxy S24 Ultra

Galaxy S21 5G
Galaxy S21 5G
Starting at

Refurbished price:£133.00

Versus £829.00 new

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Galaxy S24 Ultra
Galaxy S24 Ultra
Starting at

Refurbished price:£422.00

Versus £1,357.64 new

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Ratings

The Samsung Galaxy S21 5G, released in January 2021, and the Samsung Galaxy S24 Ultra, launched in January 2024, represent different generations within Samsung's premium smartphone lineup. While both devices operate on the Android platform with Samsung's One UI, the three-year gap introduces significant advancements in hardware, software support, and overall capabilities. The S24 Ultra builds upon the foundation laid by its predecessors, offering a more refined and feature-rich experience compared to the S21 5G.

Scores

Durability

The longevity of a smartphone is influenced by its physical resilience and ongoing software support. The Galaxy S21 5G, released in early 2021, has received a commendable level of software support, typically offering four major Android OS updates and five years of security updates. This means its major OS updates concluded around early 2025, with security updates extending into early 2026.

  • Software Support: The Galaxy S24 Ultra benefits from Samsung's extended commitment to software longevity, promising seven generations of Android OS upgrades and seven years of security updates from its 2024 release. This significantly extends its usable lifespan compared to the S21 5G.
  • Physical Durability: Both devices feature an IP68 rating for dust and water resistance, indicating protection against immersion. The S21 5G utilizes Gorilla Glass Victus for screen protection, while the S24 Ultra introduces Gorilla Armor, offering enhanced scratch resistance and durability. The S24 Ultra also features a titanium frame, contributing to its robust build.
  • Repairability: The Galaxy S21 5G generally received a repairability score in the range of 7.5 to 8.2 out of 10, indicating a relatively straightforward repair process for many components. The Galaxy S24 Ultra has also demonstrated a high repairability score, often rated around 9 out of 10, with components like the battery and screen being accessible, though some internal organization can add complexity.

Year of Release

2021

2024

Compatible with latest Update

Yes

Yes

OS

Android

Android

Foldable

No

No

Performance

Performance in daily use is a key differentiator between these two generations of devices, impacting everything from app responsiveness to demanding tasks like gaming and video editing. The Galaxy S21 5G, with its earlier generation processor and 8GB of RAM, handles everyday applications smoothly and efficiently.

  • Processing Power: The Galaxy S24 Ultra features a significantly more advanced processor, which translates to noticeably faster app loading times, smoother multitasking, and superior performance in graphically intensive games and complex applications. This enhanced processing capability also supports advanced on-device AI features.
  • Multitasking and Responsiveness: With 12GB of RAM as standard, the S24 Ultra offers greater headroom for keeping multiple applications open simultaneously without slowdowns, providing a more fluid user experience for power users. The S21 5G, typically with 8GB of RAM, manages multitasking well for most users but may show limitations with a very high number of active applications.
  • Battery Endurance: The Galaxy S21 5G is equipped with a 4000 mAh battery, generally providing enough power for a full day of moderate use. The Galaxy S24 Ultra, with its larger 5000 mAh battery and more power-efficient components, typically offers extended battery life, often lasting beyond a full day even with heavy usage.

Memory (GB)

8 GB

12 GB

Screen quality

The display is a primary interface for smartphone interaction, and both the Galaxy S21 5G and S24 Ultra offer high-quality viewing experiences, though with notable advancements in the newer model. Both devices utilize Dynamic AMOLED 2X technology, known for its vibrant colors and deep blacks.

  • Size and Resolution: The Galaxy S21 5G features a 6.2-inch display with a Full HD+ resolution (2400 x 1080 pixels), providing a clear and sharp image for its size. The Galaxy S24 Ultra boasts a larger 6.8-inch display with a Quad HD+ resolution (3120 x 1440 pixels), offering a more expansive viewing area and finer detail.
  • Brightness and Visibility: The S21 5G reaches a peak brightness of 1300 nits, ensuring good visibility in most lighting conditions. The S24 Ultra significantly enhances this with a peak brightness of 2600 nits, making it exceptionally bright and easy to view even in direct sunlight. The S24 Ultra also incorporates an anti-reflective coating for improved outdoor use.
  • Refresh Rate: Both phones feature an adaptive refresh rate of up to 120Hz for smooth scrolling and responsive interactions. The S24 Ultra's display can dynamically adjust its refresh rate from 1Hz to 120Hz, optimizing power consumption, whereas the S21 5G's adaptive refresh rate typically ranges from 48Hz to 120Hz.

Resolution

1080 x 2400

1440 x 3120

Screen type

Dynamic AMOLED 2X

Dynamic LTPO AMOLED 2X

Audiovisual

Camera capabilities are a significant focus for premium smartphones, and both the Galaxy S21 5G and S24 Ultra deliver versatile photography and videography tools, with the S24 Ultra introducing substantial upgrades.

  • Rear Camera System: The Galaxy S21 5G features a triple-camera setup with a 12MP main sensor, a 12MP ultrawide, and a 64MP telephoto lens offering 3x hybrid optical zoom. The S24 Ultra elevates this with a quad-camera system, including a 200MP main sensor, a 12MP ultrawide, a 50MP telephoto with 5x optical zoom, and a 10MP telephoto with 3x optical zoom, providing greater flexibility and detail.
  • Photography Performance: The S21 5G captures detailed and vibrant images in good lighting, with its telephoto lens providing effective zoom for distant subjects. The S24 Ultra, with its higher megapixel count on the main sensor and improved processing, delivers enhanced detail, better low-light performance, and more natural color reproduction. Users often note the S24 Ultra's versatility across various shooting conditions.
  • Video Recording: Both devices are capable of recording video up to 8K resolution, offering high-quality footage. The S24 Ultra benefits from its more advanced processing for improved stabilization and overall video quality, making it a strong option for content creation.

Main camera

12 megapixels

200 megapixels

Front camera

10 megapixels

12 megapixels

Miscellaneous

Beyond core performance and camera, several practical features contribute to the overall user experience and differentiate these two Samsung flagships.

  • Connectivity and Ports: Both phones support 5G connectivity for fast mobile data. The S21 5G features Wi-Fi 6 and Bluetooth 5.0, while the S24 Ultra upgrades to Wi-Fi 7 and Bluetooth 5.3, offering faster and more stable wireless connections. Both devices utilize a USB-C port for charging and data transfer, but neither includes a traditional headphone jack.
  • Biometric Security: Both the Galaxy S21 5G and S24 Ultra incorporate an ultrasonic in-display fingerprint sensor for secure and convenient unlocking.
  • Design and Ergonomics: The S21 5G has a compact design with a 6.2-inch screen, weighing 169 grams, and features a plastic back with a matte finish. The S24 Ultra is a larger device with a 6.8-inch display, weighing 232 grams, and features a premium titanium frame and a flat display, which some users find more comfortable for writing and drawing. A key distinguishing feature of the S24 Ultra is the integrated S Pen stylus, offering precise input for notes, drawings, and navigation.

Weight

169 g

232 g

Screen size (in)

6.2

6.8

Mobile network

5G

5G

SIM card

Dual Physical SIM + eSIM

Dual Physical SIM + eSIM

Carrier compatibility

Unlocked

Unlocked

The Samsung Galaxy S21 5G and Galaxy S24 Ultra cater to different user needs, largely due to the generational advancements between their respective releases. Users often praise the S21 5G for its balanced performance, comfortable size, and capable camera system, especially considering its position as an older flagship. Common feedback highlights its reliable daily performance and good screen quality for its time. However, some users note that its battery life, while adequate for moderate use, may require more frequent charging for heavy users, and its software support is now concluding.

The Galaxy S24 Ultra, on the other hand, is frequently lauded for its exceptional display brightness, extended battery life, and highly versatile camera system, particularly its improved zoom capabilities and more natural image processing. Users also appreciate the integrated S Pen for productivity and the promise of seven years of software updates, which ensures long-term usability and access to the latest features. Criticisms are less common but sometimes point to its larger size and weight, which might not appeal to those preferring a more compact device.

Users prioritizing a more compact form factor, solid everyday performance, and a still-capable camera system may find the Galaxy S21 5G suitable for their needs. It remains a functional device for general use. Conversely, users who demand the latest in mobile technology, superior camera versatility, extended battery life, a larger and brighter display, and long-term software support, along with the unique functionality of the S Pen, will find the Galaxy S24 Ultra better aligned with their priorities. For those considering either device, exploring quality-assured refurbished options can provide an eco-friendly alternative.

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