Overview

- Release date: 2015, April
- Known as Microsoft Lumia 640, Microsoft Lumia 640 LTE, Microsoft Lumia 640 3G, Microsoft Lumia 640 3G Dual SIM
- Windows Phone 8.1 upgradeable to Windows 10 Creators Update
- Size of 141.3 x 72.2 x 8.8 millimeters and 145 grams

Display

- 5" HD resolution (1280 x 720)
- IPS LCD
- Screen-to-body ratio: ~67.6%
- 296 ppi density
- Corning Gorilla Glass 3
- ClearBlack display

Memory

- 8 GB mass storage
- Expandable with micro SD up to 128 GB
- 1 GB RAM (LPDDR2)

Battery

- Removable 2500 mAh battery
- 24 hours talk time (3G)

Sensors

❌ Gyroscope
✔ Accelerometer
✔ Proximity
✔ Compass
❌ Barometer

Processor

- Qualcomm Snapdragon 400 (4 Cortex-A7 up to 1.2 GHz)
- GPU: Adeno 305

Cameras

- 8 MP (f/2.2 and sensor size 1/4") and 1 MP front (f/2.4)

❌ Image Stabilizer
✔ Main LED flash
❌ Front LED flash

Sound

- Loudspeaker(s): Mono
- Microphone(s): Mono

Connectivity

- Supports LTE up to 150 Mbps
- Bluetooth 4
- Wi-Fi 802.11 b/g/n

✔ Headphone jack
❌ Type-C USB
❌ OTG USB
❌ FM Radio
✔ NFC
❌ eSIM

· 2G networks
850 / 900 / 1800 / 1900
· 3G networks
850 / 900 / 2100
· 4G networks
800 / 900 / 1800 / 2100 / 2600

Additional features

- Dual SIM version
- Glance Screen