Realme C21 smartphone was launched on 5th March 2021. The phone comes with a 6.50-inch touchscreen display with a resolution of 720x1600 pixels.Realme C21 comes with 3GB of RAM. The Realme C21 runs Android 10 and is powered by a 5000mAh battery.

As far as the cameras are concerned, the Realme C21 on the rear packs a 13-megapixel primary camera with an f/2.2 aperture; a second 2-megapixel camera with an f/2.4 aperture, and a third 2-megapixel camera with an f/2.4 aperture.

The Realme C21 runs Realme UI is based on Android 10 and packs 32GB of inbuilt storage that can be expanded via microSD card with a dedicated slot. The Realme C21 is a dual-SIM (GSM and GSM) smartphone that accepts Nano-SIM and Nano-SIM cards. The Realme C21 measures 165.20 x 76.40 x 8.90mm (height x width x thickness) and weighs 190.00 grams. It was launched in Cross Black and Cross Blue colours.

Connectivity options on the Realme C21 include Wi-Fi 802.11 b/g/n, GPS, Bluetooth v5.00, and Micro-USB. Sensors on the phone include accelerometer, ambient light sensor, proximity sensor, and fingerprint sensor.