| Hardware and OS HTC Desire 21s |
| Operating system: | Android v11 |
| Processor: | Qualcomm SM7125 Snapdragon 720G (8 nm) |
| RAM: | 8 GB |
| Internal Storage: | 128 GB |
| Display HTC Desire 21s |
| Type: | IPS LCD |
| Size: | 6.6 inches |
| Resolution: | 720 x 1600 Pixels |
| Pixel Density: | 270 ppi |
| Touchscreen: | Yes, Capacitive Touchscreen, Multi-touch |
| Aspect ratio: | 20:9 |
| Connectivity HTC Desire 21s |
| Network support: | 4G , 3G, 2G |
| WI-FI: | Yes, Wi-Fi 802.11, b/g/n |
| Gps: | Yes, with A-GPS, Glonass |
| Bluetooth: | Yes, v5.0 |
| Dual SIM: | Dual SIM, GSM GSM |
| SIM size: | SIM1: Nano, SIM2: Nano |
| USB connectivity: | Mass storage device, USB charging |
| Camera HTC Desire 21s |
| Front camera resolution: | 20 MP Primary Camera |
| Camera features: | Digital Zoom, Auto Flash, Face detection, Touch to focus |
| Flash: | Yes, LED Flash |
| Autofocus: | Yes |
| Video recording: | Yes |
| Multimedia HTC Desire 21s |
| Loudspeaker: | Yes |
| Design HTC Desire 21s |
| Height: | 164.9 mm |
| Width: | 75.7 mm |
| Thickness: | 9 mm |
| Weight: | 203 grams |
| Colours: | Dawn Orange, Twilight Black |
| Battery HTC Desire 21s |
| Capacity: | 5200 mAh |
| Type: | Lithium Polymer |
| Other HTC Desire 21s |
| Fingerprint sensor: | Yes |
| Fingerprint sensor position: | Rear |
| Other sensors: | Accelerometer, Gyro, Proximity, Compass |
