Oppo Realme C21 review

Read our full review to find out how the Oppo Realme C21 differs, what our opinion of it is and whether it's worth the money.
Added by on 07.20.21 | Last update 03.24.23
Oppo Realme C21 ревю
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3.71 / 5


Realme C21 is a spring 2021 offering - a worthy addition to the Realme brand range. It has received a bunch of improvements. The Realme C21 model is the first of the C-series to receive the European TÜV Rheinland High Reliability Certificate.

Before reading the full review, you can familiarize yourself with the detailed Oppo Realme C21 specs or watch the video below the article.


  • Release date: 2021, March 05
  • Colors: Cross Black, Cross Blue
  • Dimensions: 165.2 x 76.4 x 8.9 mm.
  • Weight: 190 g.
  • Screen: 6.5" inc, 720 x 1600, IPS LCD
  • Camera : Dual, 13MP
  • Chipset: MediaTek Helio G35 (12 nm)
  • CPU: Octa-core (4x2.3 GHz Cortex-A53 & 4x1.8 GHz Cortex-A53)
  • Memory: 32GB 3GB RAM, 64GB 4GB RAM
  • Battery: 5000, Li-Po, non-removable
  • Network: GSM / HSPA / LTE
  • Operating system: Android 10, Realme UI
  • Sensors: Fingerprint (rear-mounted), accelerometer, proximity, compass


The Realme C21 has a practical design, in the tradition of the other models in the family. You won't find shiny details or glossy finishes. The casing is made of matt plastic and has a fine texture in the form of a geometric drawing. This decision is welcome as it creates a feeling of stability. Realme C21 will not be dropped as it has slipped into your palm. Its coating furthermore does not collect marks from your fingers.

The device is comfortable to wear and a decent size. It can hardly be described as slim. The fingerprint scanner is positioned on the back. It works quickly and without error.

Realme C21 can be found in the market in two colors - black and blue. It has not received protection against moisture and dust penetration into the housing.


The smartphone offers an IPS display with a diagonal of 6.5 inches and a resolution of 720 x 1600 pixels. Its aspect ratio is standard - 20:9, and the low pixel density per inch - 270 - makes an impression. The width of the frame around the screen is typical for this price class of devices.

On the front side we see a glass with a mirrored surface. It is scratch resistant. The screen has good viewing angles without serious colour deviations when viewed at an angle.

The picture is saturated and with sufficient brightness to work comfortably indoors and outdoors.


The Realme C21 is powered by a single-core MediaTek Helio G35 system, which consists of 8 cores and is built on 12nm technology. Its cores are divided into two clusters of four. The GPU is a PowerVR GE8320.

The smartphone is available in two configurations - with 2 or 3 GB of RAM and 32 or 64 GB of storage. The latter can be increased if needed, as there is a slot provided for this purpose.

MediaTek Helio G35 is a summer 2020 system. It is not very powerful and is designed for entry-level devices. It's enough for smooth interface performance, but not for heavy gaming. You can enjoy the latter at low graphics settings.

The device comes factory with Android 10 operating system and Realme UI.


On the rear panel of the Realme C21, you'll find a triple rear camera and flash. The main module takes the pictures, the other two are low-resolution and are used for macro shots and measuring the depth of the scene.

The camera interface is standard. Well known from the manufacturer's other models. A few new modes have been added that will appeal to anyone who likes to shoot. The main modes include HDR, manual mode, portrait and night mode.

The main rear camera module is 13-megapixel and is wide-angle. It has adequate PDAF phase detection autofocus. However, there is no stabiliser. In other words, the camera shoots at a budget level. The shots become brighter and contrasty, with less detail.

With the Realme C21 in hand, you can shoot videos at a maximum resolution of 1080 pixels at 30 frames per second. Again, there's no stabiliser.

As for the selfie camera, it's single. You have a beautification and portrait mode available. You can take decent selfies with it.

Autonomous operation

Realme C21 is suitable for any user who is looking for a device with long autonomous operation. The good performance is due to the large battery capacity, low-power processor and low screen resolution.

The smartphone features a lithium polymer battery that is non-removable. It has a capacity of 5000 mAh. You get a 10 W charger with the device. A curious point is the support of reverse charging.


Realme C21 is an affordable as a price smartphone that runs Android 10 operating system. It may not have the best quality screen and may have a modest hardware platform, but it guarantees satisfactory autonomous performance. For its price, it provides reliability and comfort. A perfect choice for anyone who doesn't rely on shooting and playing heavy games. There is also a triple card slot - 2 SIM and one for more memory.

If you have decided to buy Realme C21, a good decision is to bet on a larger storage. It's very important these days - we're accumulating memories, capturing important moments, sharing information, etc.

Oppo Realme C21 video review

Disclaimer: The information presented in this article is based on our team's personal experience with the Oppo Realme C21 and third-party sources. While every effort has been made to provide accurate and reliable information, readers should keep in mind that this is a subjective assessment. The writing of this article was not paid for or sponsored by Oppo.

Richard Taylor

Richard Taylor

Richard Taylor is a technology expert and journalist based in the UK. With a degree in Computer Science from the University of Birmingham, he provides insightful analysis and expert reviews of the latest smartphones and technology. His technical expertise, passion for technology and years of experience make him a trusted source in the industry.

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