Product
Xiaomi Mi 4i
Xiaomi Mi 4i
Xiaomi Redmi Note 4X
Xiaomi Redmi Note 4X
Battery
Charging 10W wired, QC1 -
Talk time Up to 35 h (3G) -
Type Li-Ion 3120 mAh, non-removable Li-Po 4100 mAh, non-removable
Body
Build Glass front (Gorilla Glass), plastic back, plastic frame Glass front, aluminum back, aluminum frame
Dimensions 138.1 x 69.6 x 7.8 mm (5.44 x 2.74 x 0.31 in) 151 x 76 x 8.5 mm (5.94 x 2.99 x 0.33 in)
SIM Dual SIM (Micro-SIM, dual stand-by) Nano-SIM + Micro-SIM
Weight 130 g (4.59 oz) 165 g (5.82 oz)
Comms
Bluetooth 4.1, A2DP 4.2, A2DP, LE
Infrared port - Yes
NFC No No
Positioning GPS, GLONASS, BDS GPS, GLONASS, BDS
Radio Stereo FM radio FM radio
USB microUSB 2.0, OTG microUSB 2.0, OTG
WLAN Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct, hotspot Wi-Fi 802.11 a/b/g/n, Wi-Fi Direct
Display
Protection Corning scratch-resistant glass -
Resolution 1080 x 1920 pixels, 16:9 ratio (~441 ppi density) 1080 x 1920 pixels, 16:9 ratio (~401 ppi density)
Size 5.0 inches, 68.9 cm2 (~71.7% screen-to-body ratio) 5.5 inches, 83.4 cm2 (~72.7% screen-to-body ratio)
Type IPS LCD IPS LCD
Features
Sensors Accelerometer, gyro, proximity, compass Fingerprint (rear-mounted), accelerometer, gyro, proximity, compass
Launch
Announced 2015, April. Released 2015, April 2017, February. Released 2017, February
Status Discontinued Discontinued
Main Camera
Features Dual-LED dual-tone flash, panorama, HDR Dual-LED dual-tone flash, panorama, HDR
Single 13 MP, f/2.0, AF 13 MP, f/2.0, 1/3.1", 1.12µm, PDAF
Video 1080p@30fps, 480p@120fps 1080p@30fps, 720p@120fps
Memory
Card slot No microSDXC (uses shared SIM slot)
Internal 16GB 2GB RAM, 32GB 2GB RAM 16GB 3GB RAM, 32GB 3GB RAM, 64GB 4GB RAM
  eMMC 4.5 eMMC 5.1
Misc
Colors Dark Gray, Black, White, Yellow, Blue, Pink Platinum Silver, Champagne Gold, Matte Black, Hatsune Miku, Sakura Powder
Models 2015015 -
SAR 0.51 W/kg (head)     0.60 W/kg (body)     -
Network
2G bands GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2
3G bands HSDPA 850 / 1900 / 2100 HSDPA 850 / 900 / 1900 / 2100
4G bands 3, 7, 38, 39, 40, 41 1, 3, 5, 7, 38, 39, 40, 41 - Snapdragon model
Speed HSPA, LTE Cat4 150/50 Mbps HSPA 42.2/5.76 Mbps, LTE (2CA) Cat6 300/50 Mbps
Technology GSM / HSPA / LTE GSM / CDMA / HSPA / LTE
  TD-SCDMA 1, 3, 5, 7, 8, 38, 39, 40, 41 - Mediatek model
Our Tests
Battery (old) Endurance rating 67h -
Camera Photo / Video -
Display Contrast ratio: 1055:1 (nominal), 2.641 (sunlight) -
Loudspeaker Voice 63dB / Noise 65dB / Ring 68dB -
Performance Basemark X: 4875 -
Platform
Chipset Qualcomm MSM8939 Snapdragon 615 (28 nm) Qualcomm MSM8953 Snapdragon 625 (14 nm)
CPU Octa-core (4x1.7 GHz Cortex-A53 & 4x1.0 GHz Cortex-A53) Octa-core 2.0 GHz Cortex-A53
GPU Adreno 405 Adreno 506
OS Android 5.0.2 (Lollipop), MIUI 8.2 Android 6.0 (Marshmallow), upgradable to 7.0 (Nougat), MIUI 10
Selfie camera
Single 5 MP, f/1.8 5 MP, f/2.0
Video 1080p@30fps
Sound
3.5mm jack Yes Yes
Loudspeaker Yes Yes
  - 24-bit/192kHz audio