MaxCom Comfort MM831 3G vs MaxCom Comfort MK399
| Type | Clamshell | Clamshell |
| Dimensions | 99.00 x 55.00 x 17.00 mm | 108.00 x 57.00 x 20.80 mm |
| Weight | 88.00 g | 125.00 g |
| Display size | 2.40" | 2.80" |
| Display | Color / TFT 256k colors 240 x 320 px (2.40") 167 ppi | Color / TFT 64k colors 240 x 320 px (2.80") 143 ppi |
| Display protection |   | |
| Additional display | | Color / TFT 64k colors 128 x 128 px (1.44") |
| Protection of the secondary display | | |
| Talk time (max.) | 2G: 240 min. (4.0 h) |  |
| Stand-by (max.) | 2G: 150 h. (6.3 days) | |
| Standard battery | Li-Ion 1000 mAhBuy powerbank
| Li-Ion 1600 mAhBuy powerbank
|
| Quick battery charging | | |
| Wireless battery charging | | |
| Internal memory | 1 GB | 4 GB |
| RAM memory | | 512 MB |
| Memory cards |  up to 32 GBBuy memory card | microSD, microSDHC, microSDXC up to 32 GBBuy memory card |
| Operating system | - | KaiOS 2.5 |
| Processor | - | Spreadtrum SC9820E |
| Processor clock | - | 1200 MHz |
| GPU | - | ARM Mali-T820 MP1 |
| Touchscreen | | |
| SAR (10g) | 1,45 W/kg | |
| DualSIM | | |
| Announced | | 1Q 2022 |
| Other names | - | - |
| GSM frequencies | 850 900 1800 1900 | 900 1800 |
| UMTS | 900 1900 | 900 2100 |
| LTE standard | | FDD LTE: 2600, 2100, 1800, 900, 850, 800 TDD LTE: 2600 |
| Standard 5G | | |
| CDMA | | |
| Standard TD-SCDMA | | |
| UMA | | |
CAMERAS - BACK
| First camera | | |
| Photo matrix | 2 Mpx | 2 Mpx |
| Resolution | 1600x1200 px | 1600x1200 px |
| Optical zoom | | |
| Flash | | |
| Dual-colour LED flash | | |
| Video formats | MPEG4, H.263, H.264 | |
| 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 | |
| HSCSD | | |
| HSDPA | | |
| HSUPA | | |
| HSPA | | |
| HSPA+ | | |
| LTE DL | | |
| LTE UP | | |
| WIMAX+ | | |
| GPRS | | |
| EDGE | | |
| Bluetooth | | |
| HDMI | | |
| WiFi | | v802.11 b/g/n |
| WiFi frequencies | | 2,4 GHz |
| WiFi Direct | | |
| WiFi Display | | |
| DLNA | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v2.0 | |
| GPS | | |
| A-GPS | | |
| GLONASS | | |
| Beidou | | |
| Galileo | | |
| QZSS | | |
| NFC | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | | |
| Swype | | |
| e-mail client | | POP3, IMAP4, SMTP |
| Hardware QWERTY keyboard | | |
| RSS Reader | | |
Multimedia
| Radio | | |
| MP3 | | |
| Stereo speakers | | |
| Audio Jack | 3.5 mm | 3.5 mm |
| HD Voice | | |
| Sound formats | AAC, AAC+, AMR, WAV, eAAC+ | |
| Polyphony | | |
| Video ringtone | | |
| Ring composer | | |
| Games | | |
| Java | | |
| Videophone | | |
| DVB-H television | | |
| TV-Out | | |
PIM AND ADDITIONAL FUNCTIONS
| Watch | | |
| Alarm | | |
| Calculator | | |
| Currency converter | | |
| Organizer | | |
| Calendar | | |
| Flight mode | | |
| SyncML | | |
| Data and fax | | |
| Screensaver | | |
| Themes | | |
| Interchangeable covers | | |
| Voice dial | | |
| Speakerphone | | |
| Recorder | | |
| Vibrations | | |