Microsoft Lumia 640 LTE vs Xiaomi Mi4i
| Type | Touch | Touch |
| Dimensions | 141.30 x 72.20 x 8.80 mm | 138.10 x 69.60 x 7.80 mm |
| Weight | 145.00 g | 149.00 g |
| Display size | 5.00" | 5.00" |
| Display | Color / IPS TFT 16M colors 720 x 1280 px (5.00") 294 ppi | Color / JDI TFT 16M colors 1080 x 1920 px (5.00") 441 ppi |
| Display protection | Corning Gorilla Glass Buy screen protector
 |  |
| Additional display | | |
| Protection of the secondary display | | |
| Talk time (max.) | 2G: 1590 min. (26.5 h) 3G: 1050 min. (17.5 h) |  |
| Stand-by (max.) | 2G: 864 h. (36.0 days) | |
| Playback time (max.) | Audio: 86 h (3.6 days) Video: 8,6 h (0.3 days) | nd |
| Internet browsing time (max.) | WiFi: 10,8 h (0.4 days) | nd |
| Standard battery | Li-Ion 2500 mAhBuy powerbank
| Li-Po 3120 mAhBuy powerbank
|
| Quick battery charging | | |
| Wireless battery charging | | |
| Internal memory | 8 GB | 16 GB |
| RAM memory | 1 GB | 2 GB |
| Memory cards |  microSD, microSDHC, microSDXC up to 128 GBBuy memory card | |
| Operating system | MS Windows Phone 8.1 | Android 5.0 Lollipop |
| Processor | Qualcomm Snapdragon 400 | Qualcomm Snapdragon 615 8939 |
| Processor clock | 1200 MHz | 1700 MHz |
| GPU | Adreno 305 | Adreno 405 |
| Touchscreen | | |
| SAR (10g) | | 0,598 W/kg |
| DualSIM | | |
| SIM cards standard | SingleSIM(microSIM) | DualSIM(microSIM, microSIM) |
| Hybrid DualSIM | nd | |
| Announced | 1Q 2015 | 2Q 2015 |
| Other names | - | Mi 4i |
| GSM frequencies | 850 900 1800 1900 | 850 900 1800 1900 |
| UMTS | 850 900 2100 | 850 1900 2100 |
| LTE standard | FDD LTE: 2600, 2100, 1800, 900, 800 | FDD LTE: 2600, 1800 TDD LTE: 2600, 2500, 2300, 1900 |
| CDMA | | |
| Standard TD-SCDMA | | 1900 2000 |
| UMA | | |
CAMERAS - BACK
| First camera | | |
| Photo matrix | 8 Mpx | 13 Mpx |
| Resolution | 3264x2448 px | 4128x3096 px |
| Optical zoom | | |
| Flash | LED | 2x LED |
| Dual-colour LED flash | | 1+1 |
| Video resolution | 1920x1080 px | 1920x1080 px |
| Video formats | MPEG4, H.263, H.264 | H.263, H.264, MPEG4 |
| Additional | AF | AF, f/2.0 |
CAMERAS - FRONT
| First camera | | |
| Photo matrix | 0.9 Mpx | 5 Mpx |
| Optical zoom | | |
| Flash | | |
| Dual-colour LED flash | | |
| Video formats | MPEG4, H.263, H.264 | H.263, H.264, MPEG4 |
| Additional | - | f/1.8 |
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 | | |
| HSDPA | 42.20 Mbit/s | 42.00 Mbit/s |
| HSUPA | 5.76 Mbit/s | 5.76 Mbit/s |
| HSPA | | |
| HSPA+ | | |
| LTE DL | | |
| LTE UP | | |
| WIMAX+ | | |
| GPRS | | |
| EDGE | | |
| Bluetooth | v4.0 | v4.1 |
| A2DP Profile | | |
| HDMI | | |
| WiFi | v802.11 b/g/n | v802.11 a/b/g/n/ac |
| WiFi frequencies | 2,4 GHz | 2,4 GHz; 5 GHz |
| WiFi Direct | | |
| WiFi Display | | |
| DLNA | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v2.0 | v2.0 |
| GPS | | |
| A-GPS | | |
| GLONASS | | |
| Beidou | | |
| NFC | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | XT9 | XT9 |
| Swype | | |
| e-mail client | POP3, IMAP4, SMTP | 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+ | AAC, AAC+, AMR, APE, FLAC, WAV, eAAC+ |
| Polyphony | | |
| Video ringtone | | |
| Ring composer | | |
| Games | | |
| Java | | ART |
| 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 | | |