realme C21

realme C21 – superb value, Optus locked (review)

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realme is one of the fastest-growing smartphone brands. Its success is in focusing on the youth market. The realme C21 (Optus locked) is a $199 4G smartphone offering terrific features for the price. It is even better with the $30 credit when you sign up with Optus.

For starters, the realme C21 has a 5000mAh battery (big), a 6.5” colourful screen, a 13MP triple camera, and even has NFC. Not to get too techy, but most phones at this price sacrifice memory (this has 4GB) and storage (64GB), a dedicated microSD slot (to 256GB), and runs the full 64-bit Android 10. We will do a mini-review as at $199; all you are focusing on is a good reliable phone, decent social media class camera and two-day battery life.

Summary: It is a low cost, more so with the Optus $30 incentive, well-made phone with everything you can expect plus NFC and a 5000mAh battery. Add to that realme’s build quality, and it’s a <$200  winner.

realme C21 Model RMX3201 Optus Locked

  • Website here
  • Price: $199 includes a free $30 recharge when you first activate the sim
  • From: Big W ($179), Target ($199) (only genuine resellers*)
  • Warranty: 2-years ACL (outstanding)
  • Country of manufacture: China
  • realme is a youth-focused, online-only brand with the mantra ‘Dare To Leap’. So, if you are a Millennial or an old fart, don’t let youth have all the fun.
  • Other realme reviews here

* Do not buy the 3/32GB version as it is not for Australia and only runs 32-bit Android, which is painfully slow.

Processor MediaTek Helio G35  (12 nm) – fast enough

  • Geekbench 5 single/multi-core is 169/981. It can play most low-level games.
  • Throttle: 95,772GIPS, Average 90,744GIPS, 8% throttle
  • 64GB eMMC (43GB free) Androbecnhc sequential read/write 296/227MBps
  • It is a micro-USB 2.0 480Mbps half-duplex. OTG data transfer tops out at 30/30MBps.

Its closest competitor is an entry-level Qualcomm SD429.

Screen – 1600×720, 20:9, IPS – great colour

It has 400nit (tested to 425), so it is bright enough. Tempered glass resists scratches.

Comms – NFC is a huge bonus

  • Wi-Fi 4 N maximum speed -37dBm/86Mbps half-duplex (not great but gets the job done)
  • BT  5.0 with SBC codec and connects to headphones and as a handsfree device
  • NFC – yes
  • GPS – single antenna <6m accuracy
  • FM radio needs 3.5mm buds to act as aerial
  • Rear fingerprint reader

Battery 5000mAh – good for two days

  • GFX Bench Manhattan: 883.6minutes (14.73 hours) and 668 frames
  • GFX Bench T-Rex: 889.2min (14.82 hours) and 1599 frames
  • PC Mark 2.0 battery test: 14hour and 47 minutes
  • Battery charge – 5V/2A/10W micro-USB is slow over four hours (off) and five hours (on).

It uses the outdated micro-USB cable to save cost as it does not need USB-C PD charging circuitry.

Sound – mono

It has a mono earpiece and a rear-firing speaker. It has a 3.5mm combo audio jack. Sound is mid-centric for clear voice. It has BT 5.0 and only supports the SBC codec. The feed was loud and clean to our reference headphones.

Build – Polycarbonate with a nice cross-hatch non-slip back

It is 165.2 x 76.4 x 8.9 mm x 190g and uses a polycarbonate back and frame. Interestingly it has been TUV tested and has a 3-year life cycle rating.

Colours are Cross Black, Cross Blue

Android 10 – as good as you will get

It is unlikely that you will get Android 11. It is overlaid with realme 1.0 UI  (previously used OPPO ColorOS) that is easy to use and youth-focused.  

realme C21 Camera

It is a capable camera remembering that the bigger 48/64MP cameras ‘bin’ to 12/16MP anyway. What it lacks is the AI Power to turn poor shots into good ones.

  • 13 MP, f/2.2, 26mm (wide), 1/3.06″, 1.12µm, PDAF, 4x digital, 1080p@30, 69.5° FOV, Sensor likely Samsung ISOCELL 3L8
  • 2 MP, f/2.4, 1.75umn, 4cm FF (macro) Omnivision OV02A1B sensor
  • 2 MP, f/2.4, 1.75um, FF (depth) Galaxycore CD2375H sensor,
  • Selfie – 5 MP, f/2.2, (wide), 1/5.0″, 1.12µm 1080p@30 contrast AF, Galaxycore 5035 sensor
realme C21
1X – a great shot given it was an overcast day
realme C21
4X zoom – not bad with just a little noise in the forest background
realme C21
Superb macro shot
realme C21
<40 lumen and this is not a bad shot – the monitor screens are blown out
realme C21
Night mode and the detail and colours return with excessive noise

GadgetGuy’s take

The realme C21 fills the niche for a well-made, reasonable performance, budget phone. It is locked to Optus, and you get a $30 bonus when you activate the supplied SIM. I expect you can also use Optus MVNO’s as well, and you can unlock the phone later for a fee.


Moto G10 64GB NFC $249 is worth a look.

realme C21 is rated as a $199 4G smartphone with a $30 credit

It meets or exceeds all specifications for this price, so we start at 8/10. Add points for the two-year warranty, realme build quality, NFC, 3.5mm combo audio, 64-bit Android, 5000mAh battery, great camera – it is very good. Take points off for USB-C and carrier locking. 9/10

realme C21
The realme C21 fills the niche for a well-made, reasonable performance, budget phone.
Value for money
Ease of use
You won't find better value
Optus locked
micro-USB means slow charging