Asus J121 vs Asus J103
| Type | Clamshell | Clamshell |
| Dimensions | 80.00 x 40.00 x 20.50 mm | 82.00 x 42.00 x 23.50 mm |
| Weight | 80.00 g | 80.00 g |
| Display size | 1.80" | 1.80" |
| Display | Color / TFT 256k colors 128 x 160 px (1.80") | Color / TFT 256k colors 128 x 160 px (1.80") |
| Display protection |   | |
| Additional display | Color / CSTN 64k colors 96 x 64 px (1.00") | Color / TFT 256k colors 128 x 128 px (1.10") |
| Protection of the secondary display | | |
| Talk time (max.) | 2G: 300 min. (5.0 h) | 2G: 180 min. (3.0 h) |
| Stand-by (max.) | 2G: 300 h. (12.5 days) | 2G: 150 h. (6.3 days) |
| Standard battery | Li-Ion 720 mAhBuy powerbank
|  |
| Quick battery charging | | |
| Wireless battery charging | | |
| Phonebook memory | 300 places | 300 places |
| Internal memory | 64 MB | |
| Memory cards | | |
| Touchscreen | | |
| SAR (10g) | 1,15 W/kg | |
| DualSIM | | |
| Announced | 1Q 2005 | |
| Other names | - | - |
| GSM frequencies | 900 1800 1900 | 900 1800 1900 |
| UMTS | | |
| LTE standard | | |
| CDMA | | |
| Standard TD-SCDMA | | |
| UMA | | |
CAMERAS - BACK
| First camera |  | |
| Photo matrix | 0.3 Mpx | 0.3 Mpx |
| Resolution | 640x480 px | |
| Optical zoom | | |
| Flash | | LED |
| Dual-colour LED flash | | |
| Video formats | H.263, MPEG4, 3GP | |
| Additional | - | - |
CAMERAS - FRONT
SENSORS
| Accelerometer | | |
| Proximity | | |
| Light | | |
| Magnetometer | | |
| Gyroscope | | |
| Barometer | | |
| Altimeter | | |
| Gravity | | |
| Hall-effect | | |
| Iris scanner | | |
| Fingerprint scanner | | |
| Thermometer | | |
| Hygrometer | | |
Data transfer
| xHTML | | |
| WAP | v2.0 | v2.0 |
| HSCSD | | |
| HSUPA | | |
| HSPA | | |
| HSPA+ | | |
| LTE DL | | |
| LTE UP | | |
| WIMAX+ | | |
| GPRS | class 10 | class 10 |
| EDGE | | |
| Bluetooth | | |
| HDMI | | |
| WiFi | | |
| WiFi frequencies | | |
| WiFi Direct | | |
| WiFi Display | | |
| DLNA | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v1.1 | |
| Beidou | | |
| NFC | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | | |
| Swype | | |
| e-mail client | | |
| Hardware QWERTY keyboard | | |
| RSS Reader | | |
Multimedia
| Radio | | |
| MP3 | | |
| Stereo speakers | | |
| Audio Jack | | |
| HD Voice | | |
| Sound formats | AAC | |
| Polyphony | 64 voices | 64 voices |
| Video ringtone | | |
| Ring composer | | |
| Games | | |
| Java | MIDP 1.0 | MIDP 1.0 |
| Videophone | | |
| DVB-H television | | |
| TV-Out | | |
PIM AND ADDITIONAL FUNCTIONS
| Watch | | |
| Stopwatch | | |
| Alarm | | |
| Calculator | | |
| Currency converter | | |
| Organizer | | |
| Calendar | | |
| Flight mode | | |
| SyncML | | |
| Data and fax | | |
| Screensaver | | |
| Themes | | |
| Interchangeable covers | | |
| Voice dial | | |
| Speakerphone | | |
| Recorder | | |
| Vibrations | | |