| Manufacture | BenQ-Siemens |
| Model | C81 |
| Form factor | Block |
| Weight | 90 gram |
| Dimensions (HxWxD) | 104 x 47 x 18 |
| Operating System | Other |
| Networks | 2G - 900/1800/1900
|
| HSCSD |  |
| GPRS |  |
| EDGE | |
| UMTS | |
| HSDPA | |
| HSPA+ | |
| WiMAX | |
| LTE (4G light) | |
| WLAN / Wi-Fi | |
| Wi-Fi Hotspot | |
| Wi-Fi Direct | |
| SMS | |
| MMS | |
| Email | |
| HDMI out | |
| USB port | |
| MHL | |
| Bluetooth | |
| Bluetooth version | NA |
| DLNA | |
| GPS | |
| Glonass | |
| ANT+ | |
| IrDA | |
| NFC | |
| 3.5 mm audio connector | |
| Camera | |
| Camera resolution | 1.3 Megapixels, 5x digital zoom |
| Image Stabilization | |
| BSI sensor | |
| Camera Flash/Light | |
| Flash type | NA |
| Video recording | |
| Video capture resolution | NA |
| Second Camera | NA |
| Display size | 1.8 inches |
| Touchscreen | |
| Colour display | |
| Number of colours | 262144 |
| Display width | 132 |
| Display height | 176 |
| PPI | 122.22 |
| Second Display | NA |
| CPU | NA |
| GPU | NA |
| Memory | 27 MB, Expandable with RS MMC |
| Micro SIM | |
| Dual SIM | |
| MP3 | |
| Ringtones / Music file format | Polyphonic 64 voices |
| Java | |
| Games | Yes |
| FM Radio | |
| Battery | Li-Ion 820 mAh |
| Standby time (h) | 300 |
| Talktime (m) | 300 |
| Wireless Charging | |
| Browser | 2.0 |
| Calendar | |
| Voicedialing | |
| IP Code | NA |
| Predictive text | |
| RSS reader | |
| Voicememo | |
| PC Synchronization | |
| SyncML | |
| Website | Website |
