| Hardware and OS | Karbonn Titanium S21 | |
| Operating System | Android v4.4.2 (Kitkat) | |
| Processor | Quad core, 1.2 GHz | |
| RAM | 512 MB | |
| Internal Memory | 4 GB | |
| Expandable Memory | yes Up to 32 GB | |
| SIM Slot(s) | Dual SIM, GSM GSM | |
| Display | Karbonn Titanium S21 | other phones |
| Screen Size | 4.5 inches (11.43 cm) | |
| Screen Resolution | 480 x 854 pixels | |
| Display Type | TFT | |
| Pixel Density | 218 ppi | |
| Screen Protection | No | |
| Touch Screen | yes Capacitive Touchscreen, Multi-touch | |
| Main Camera | Karbonn Titanium S21 | other phones |
| Resolution | 3.2 MP Primary Camera
| |
| Image Resolution | 2048 x 1536 Pixels | |
| Flash | yes LED Flash | |
| Camera Features | Digital Zoom | |
| Autofocus | No | |
| Optical Image Stabilisation | No | |
| Front Camera | Karbonn Titanium S21 | other phones |
| Resolution | 0.3 MP Primary Camera
| |
| Flash | No | |
| Autofocus | No | |
| Connectivity | Karbonn Titanium S21 | other phones |
| Network | 4G: Not Available,
3G: Available, 2G: Available | |
| SIM 1 | 3G Bands: UMTS 2100 MHz 2G Bands: GSM 1800 / 900 MHz
GPRS: Available EDGE: Available | |
| SIM 2 | 2G Bands: GSM 1800 / 900 MHz
| |
| Bluetooth | yes | |
| GPS | yes with A-GPS | |
| NFC | No | |
| Wi-Fi | yes Wi-Fi 802.11, b/g/n | |
| Wi-Fi Features | Mobile Hotspot | |
| USB Connectivity | microUSB 2.0 | |
| Multimedia | Karbonn Titanium S21 | other phones |
| Audio Jack | 3.5 mm | |
| FM Radio | yes | |
| Loudspeaker | yes | |
| Design | Karbonn Titanium S21 | other phones |
| Height | 134 mm | |
| Width | 68 mm | |
| Thickness | 10 mm | |
| Weight | 118 grams | |
| Colours | Blue, Grey | |
| Battery | Karbonn Titanium S21 | other phones |
| Type | Li-ion | |
| Capacity | 1600 mAh | |
| User Replaceable | yes | |
| Quick Charging | No | |
| Standby time | Up to 136 Hours(2G) | |
| TalkTime | Up to 3 Hours(2G) | |
| USB Type-C | No | |
| Features | Karbonn Titanium S21 | other phones |
| Fingerprint Sensor | No | |
| Other Sensors | Proximity sensor, Accelerometer | |
