Product
Vivo Y81i
Vivo Y81i
Xiaomi Redmi Note 7S
Xiaomi Redmi Note 7S
Battery
Charging - 18W wired, QC4
Type 3260 mAh, non-removable Li-Po 4000 mAh, non-removable
Body
Build Glass front (Gorilla Glass), plastic back, plastic frame Glass front (Gorilla Glass 5), glass back (Gorilla Glass 5), plastic frame
Dimensions 155.1 x 75 x 7.8 mm (6.11 x 2.95 x 0.31 in) 159.2 x 75.2 x 8.1 mm (6.27 x 2.96 x 0.32 in)
SIM Nano-SIM + Nano-SIM Nano-SIM + Nano-SIM
Weight 143 g (5.04 oz) 186 g (6.56 oz)
  - Splash resistant
Comms
Bluetooth 5.0, A2DP, LE 5.0, A2DP, LE
Infrared port - Yes
NFC No No
Positioning GPS, GLONASS, BDS GPS, GLONASS, BDS
Radio FM radio FM radio, recording
USB microUSB 2.0, OTG USB Type-C 2.0
WLAN Wi-Fi 802.11 b/g/n, Wi-Fi Direct Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct
Display
Protection Corning Gorilla Glass Corning Gorilla Glass 5
Resolution 720 x 1520 pixels, 19:9 ratio (~270 ppi density) 1080 x 2340 pixels, 19.5:9 ratio (~409 ppi density)
Size 6.22 inches, 96.6 cm2 (~83.0% screen-to-body ratio) 6.3 inches, 97.4 cm2 (~81.4% screen-to-body ratio)
Type IPS LCD IPS LCD
Features
Sensors Accelerometer, proximity, compass Fingerprint (rear-mounted), accelerometer, gyro, proximity, compass
Launch
Announced 2018, October. Released 2018, November 2019, May. Released 2019, May
Status Discontinued Discontinued
Main Camera
Dual - 48 MP, f/1.8, (wide), 1/2.0", 0.8µm, PDAF 5 MP, f/2.2, (depth)
Features LED flash, HDR, panorama Dual-LED flash, HDR, panorama
Single 13 MP, f/2.2, PDAF -
Video 1080p@30fps 1080p@30/60/120fps, (gyro-EIS)
Memory
Card slot microSDXC (dedicated slot) microSDXC (uses shared SIM slot)
Internal 16GB 2GB RAM 32GB 3GB RAM, 64GB 4GB RAM
  eMMC 5.1 eMMC 5.1
Misc
Colors Black, Red Onyx Black, Sapphire Blue, Ruby Red, Astro White
Models 1812, 1812_19 M1901F71
Network
2G bands GSM 850 / 900 / 1800 / 1900 GSM 850 / 900 / 1800 / 1900
3G bands HSDPA 850 / 900 / 2100 HSDPA 850 / 900 / 1900 / 2100
4G bands 1, 3, 5, 7, 8, 38, 40, 41 1, 3, 5, 8, 40, 41
Speed HSPA 21.1/5.76 Mbps, LTE (2CA) Cat7 300/150 Mbps HSPA 42.2/5.76 Mbps, LTE (2CA) Cat12 600/150 Mbps
Technology GSM / HSPA / LTE GSM / HSPA / LTE
Platform
Chipset Mediatek MT6761 Helio A22 (12 nm) Qualcomm SDM660 Snapdragon 660 (14 nm)
CPU Quad-core 2.0 GHz Cortex-A53 Octa-core (4x2.2 GHz Kryo 260 Gold & 4x1.8 GHz Kryo 260 Silver)
GPU PowerVR GE8320 Adreno 512
OS Android 8.1 (Oreo), Funtouch 4 Android 9.0 (Pie), planned upgrade to Android 10, MIUI 12
Selfie camera
Features - HDR
Single 5 MP, f/2.2 13 MP, f/2.0, (wide), 1/3.1", 1.12µm
Video 1080p@30fps
Sound
3.5mm jack Yes Yes
Loudspeaker Yes Yes