| Manufacture | Nokia | Sony |
| Model | 6555 | Xperia U |
| Form factor | Clamshell/fold | Block |
| Weight | 97 gram | 110.00 |
| Dimensions (HxWxD) | 100 x 44 x 20 | 112.00 x 54.00 x 12.00 |
| Operating System | Series 40 | Android |
| Networks | 2G - 850/900/1800/1900
| 2G - 850/900/1800/1900
3G - 900/2100 |
| 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 | 3.0 |
| DLNA | | |
| GPS | | |
| Glonass | | |
| ANT+ | | |
| IrDA | | |
| NFC | | |
| 3.5 mm audio connector | | |
| Camera | | |
| Camera resolution | 1.3 Megapixels, 6x digital zoom | 5 megapixel, autofocus, 16x digital zoom, face detection |
| Image Stabilization | | |
| BSI sensor | | |
| Camera Flash/Light | | |
| Flash type | NA | NA |
| Video recording | | |
| Video capture resolution | NA | 720p |
| Second Camera | NA | VGA (640 x 480) |
| Display size | 2 inches | 3.50 |
| Touchscreen | | |
| Colour display | | |
| Number of colours | 16000000 | 16000000 |
| Display width | 240 | 480 |
| Display height | 320 | 854 |
| PPI | 200 | 279.90 |
| Second Display | NA | NA |
| CPU | NA | 1 GHz dual core ST-Ericsson U8500 processor |
| GPU | NA | DB8500 |
| Memory | 30 MB. Expandable up to 4 GB with MicroSD. 2GB included | 512 MB. 4 GB storage. Expandable up to 32 GB using microSD card |
| Micro SIM | | |
| Dual SIM | | |
| MP3 | | |
| Ringtones / Music file format | Polyphonic, MP3, AAC eAAC+ WMA | MP3, AAC, WMF, WAV, OTA, OGG |
| Java | | |
| Games | 4 | Yes |
| FM Radio | | |
| Battery | 1020 mAh | 1320 mAh |
| Standby time (h) | 300 | 472 |
| Talktime (m) | 390 | 396 |
| Wireless Charging | | |
| Browser | 2.0 XHTML | Android HTML Webkit |
| Calendar | | |
| Voicedialing | | |
| IP Code | NA | NA |
| Predictive text | | |
| RSS reader | | |
| Voicememo | | |
| PC Synchronization | | |
| SyncML | | |
| Website | Website | Website |
