| Hardware and OS | Celkon A21 | |
| Operating system | Android 4.2.2 (Jelly Bean) | |
| Processor | Quad-core 1.3 GHz Cortex-A7 | |
| Chipset | Mediatek MT6582 (28 nm) | |
| GPU | Mali-400MP2 | |
| Internal memory | 512 MB, 256 MB RAM | |
| External memory | microSD, up to 32 GB | |
| Display | Celkon A21 | other phones |
| Size | 4" inc | |
| Resolution | 320 x 480 px | |
| Touchscreen | capacitive touchscreen | |
| Screen-to-Body Ratio | 57.8% | |
| Display area | 47.6 cm2 | |
| Display aspect ratio | 3:2 (height:width) | |
| Pixel Density | 144 PPI | |
| Connectivity | Celkon A21 | other phones |
| 2G Network | GSM 900 / 1800 - SIM 1 & SIM 2 | |
| Wi-Fi | Wi-Fi 802.11 b/g/n | |
| Network | GSM / HSPA | |
| SIM card | Dual SIM (Dual stand-by) | |
| Bluetooth | 4.0, A2DP | |
| Edge | Yes | |
| GPRS | Yes | |
| GPS | No | |
| Speed | HSPA | |
| USB | microUSB | |
| Camera | Celkon A21 | other phones |
| Main camera | 3.15 MP, Single | |
| Specs | 3.15 MP | |
| Video | Yes | |
| Selfie camera | 1.3 MP, Single | |
| Multimedia | Celkon A21 | other phones |
| 3.5 mm Jack | Yes | |
| Radio | FM radio | |
| Design | Celkon A21 | other phones |
| Colors | Black, Blue, Red | |
| Dimensions | 124.8 x 66.1 x 10.8 mm | |
| Weight | 115.3 g | |
| Battery | Celkon A21 | other phones |
| Battery capacity | 1500 mAh, Li-Ion | |
| Battery life | Stand by time- Up to 120 h (3G)
Talking time- Up to 8 h (3G)
| |
| Other | Celkon A21 | other phones |
| SAR | SAR EU - 0.99 W/kg (head) 1.39 W/kg (body) | |
| Release date | 2014 | |
| Sensors | Accelerometer | |
