Product
Vivo Y81i
Vivo Y81i
Vivo Y15
Vivo Y15
Battery
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) 159.4 x 76.8 x 8.9 mm (6.28 x 3.02 x 0.35 in)
SIM Nano-SIM + Nano-SIM Nano-SIM + Nano-SIM
Weight 143 g (5.04 oz) 190.5 g (6.74 oz)
Comms
Bluetooth 5.0, A2DP, LE 5.0, A2DP, LE
NFC No No
Positioning GPS, GLONASS, BDS GPS, GLONASS, GALILEO, 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 b/g/n, Wi-Fi Direct
Display
Protection Corning Gorilla Glass -
Resolution 720 x 1520 pixels, 19:9 ratio (~270 ppi density) 720 x 1544 pixels, 19.3:9 ratio (~268 ppi density)
Size 6.22 inches, 96.6 cm2 (~83.0% screen-to-body ratio) 6.35 inches, 99.6 cm2 (~81.4% screen-to-body ratio)
Type IPS LCD IPS LCD
Features
Sensors Accelerometer, proximity, compass Fingerprint (rear-mounted), accelerometer, proximity, compass
Launch
Announced 2018, October. Released 2018, November 2019, May 28. Released 2019, May
Status Discontinued Discontinued
Main Camera
Features LED flash, HDR, panorama LED flash, HDR, panorama
Single 13 MP, f/2.2, PDAF -
Triple - 13 MP, f/2.2, PDAF 8 MP, f/2.2, 16mm (ultrawide) 2 MP, f/2.4, (depth)
Video 1080p@30fps 1080p@30fps
Memory
Card slot microSDXC (dedicated slot) microSDXC (dedicated slot)
Internal 16GB 2GB RAM 64GB 4GB RAM
  eMMC 5.1 eMMC 5.1
Misc
Colors Black, Red Aqua Blue, Burgundy Red
Models 1812, 1812_19 -
SAR - 1.01 W/kg (head)     0.75 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, 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) Cat6 300/50 Mbps
Technology GSM / HSPA / LTE GSM / HSPA / LTE
Platform
Chipset Mediatek MT6761 Helio A22 (12 nm) Mediatek MT6762 Helio P22 (12 nm)
CPU Quad-core 2.0 GHz Cortex-A53 Octa-core 2.0 GHz Cortex-A53
GPU PowerVR GE8320 PowerVR GE8320
OS Android 8.1 (Oreo), Funtouch 4 Android 9.0 (Pie), Funtouch 9
Selfie camera
Single 5 MP, f/2.2 16 MP, f/2.0, 26mm (wide), 1/3.06", 1.0µm
Video 1080p@30fps
Sound
3.5mm jack Yes Yes
Loudspeaker Yes Yes