Product
Vivo Y81i
Vivo Y81i
Vivo Z1Pro
Vivo Z1Pro
Battery
Charging - 18W wired
Type 3260 mAh, non-removable 5000 mAh, non-removable
Body
Build Glass front (Gorilla Glass), plastic back, plastic frame Glass front, plastic back, plastic frame
Dimensions 155.1 x 75 x 7.8 mm (6.11 x 2.95 x 0.31 in) 162.4 x 77.3 x 8.9 mm (6.39 x 3.04 x 0.35 in)
SIM Nano-SIM + Nano-SIM Nano-SIM + Nano-SIM
Weight 143 g (5.04 oz) 201 g (7.09 oz)
Comms
Bluetooth 5.0, A2DP, LE 5.0, A2DP, LE
NFC No No
Positioning GPS, GLONASS, BDS GPS, GLONASS, BDS
Radio FM radio FM radio
USB microUSB 2.0, OTG microUSB 2.0, OTG
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 -
Resolution 720 x 1520 pixels, 19:9 ratio (~270 ppi density) 1080 x 2340 pixels, 19.5:9 ratio (~395 ppi density)
Size 6.22 inches, 96.6 cm2 (~83.0% screen-to-body ratio) 6.53 inches, 104.7 cm2 (~83.4% 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, July. Released 2019, July
Status Discontinued Discontinued
Main Camera
Features LED flash, HDR, panorama LED flash, HDR, panorama
Single 13 MP, f/2.2, PDAF -
Triple - 16 MP, f/1.8, (wide), 1/2.8", 1.12µm, AF 8 MP, f/2.2, 16mm (ultrawide), 1/4.0", 1.12µm 2 MP, f/2.4, (depth)
Video 1080p@30fps 4K@30fps, 1080p@30/60fps
Memory
Card slot microSDXC (dedicated slot) microSDXC (dedicated slot)
Internal 16GB 2GB RAM 64GB 4GB RAM, 64GB 6GB RAM, 128GB 6GB RAM, 128GB 8GB RAM
  eMMC 5.1 UFS 2.1
Misc
Colors Black, Red Sonic Blue, Sonic Black, Mirror Black
Models 1812, 1812_19 1951, PD1911F_EX, 1918
SAR - 0.75 W/kg (head)     0.40 W/kg (body)    
Network
2G bands GSM 850 / 900 / 1800 / 1900 GSM 850 / 900 / 1800 / 1900
3G bands HSDPA 850 / 900 / 2100 HSDPA 850 / 900 / 2100
4G bands 1, 3, 5, 7, 8, 38, 40, 41 1, 3, 4, 5, 8, 34, 38, 39, 40, 41
Speed HSPA 21.1/5.76 Mbps, LTE (2CA) Cat7 300/150 Mbps HSPA, LTE
Technology GSM / HSPA / LTE GSM / CDMA / HSPA / LTE
  - CDMA 800 & TD-SCDMA
Our Tests
Performance - AnTuTu: 184517 (v7) GeekBench: 6001 (v4.4) GFXBench: 13fps (ES 3.1 onscreen)
Platform
Chipset Mediatek MT6761 Helio A22 (12 nm) Qualcomm SDM712 Snapdragon 712 (10 nm)
CPU Quad-core 2.0 GHz Cortex-A53 Octa-core (2x2.3 GHz Kryo 360 Gold & 6x1.7 GHz Kryo 360 Silver)
GPU PowerVR GE8320 Adreno 616
OS Android 8.1 (Oreo), Funtouch 4 Android 9.0 (Pie), upgradable to Android 10, Funtouch 10
Selfie camera
Features - HDR
Single 5 MP, f/2.2 32 MP, f/2.0, 26mm (wide), 1/2.8", 0.8µm
Video 1080p@60fps
Sound
3.5mm jack Yes Yes
Loudspeaker Yes Yes