| Hardware and OS | vivo Y31s 5G | Oppo A3s |
| Operating system | Android 11, Funtouch 10.5 | Android 8.1 (Oreo); ColorOS 5.1 |
| Processor | Octa-core (2x2.0 GHz Kryo 460 & 6x1.8 GHz Kryo 460) | Octa-core 1.8 GHz Cortex-A53 |
| Chipset | Qualcomm SM4350 Snapdragon 480 5G (8 nm) | Qualcomm SDM450 Snapdragon 450 (14 nm) |
| GPU | Adreno 619 | Adreno 506 |
| Internal memory | 128GB 4GB RAM, 128GB 6GB RAM | 16 GB, 2 GB RAM |
| External memory | No | microSD, up to 256 GB (dedicated slot) |
| Display | vivo Y31s 5G | Oppo A3s |
| Type | IPS LCD, 90Hz | IPS LCD |
| Size | 6.58 inches, 104.8 cm2 | 6.2" inc |
| Resolution | 1080 x 2408 pixels, 20:9 ratio | 720 x 1520 px |
| Touchscreen | | capacitive touchscreen |
| Screen-to-Body Ratio | | 81.2% |
| Display area | | 95.9 cm2 |
| Display aspect ratio | | 19:9 (height:width) |
| Pixel Density | | 271 PPI |
| Colors | | 16M |
| Main Camera | vivo Y31s 5G | Oppo A3s |
| Camera | 13 MP, f/2.2, (wide), PDAF
2 MP, f/2.4, (depth) | |
| Features | LED flash, HDR, panorama | |
| Video | 4K@30fps, 1080p@30fps | |
| Selfie camera | vivo Y31s 5G | Oppo A3s |
| Camera | 8 MP, f/2.0, (wide) | |
| Features | HDR | |
| Video | 1080p@30fps | |
| Connectivity | vivo Y31s 5G | Oppo A3s |
| 2G Network | GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 | GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 |
| 3G Network | HSDPA 850 / 900 / 1700(AWS) / 2100 | HSDPA 850 / 900 / 2100 |
| 4G Network | 1, 3, 4, 5, 8, 28, 34, 38, 39, 40, 41 | LTE |
| Wi-Fi | | Wi-Fi 802.11 b/g/n, WiFi Direct, hotspot |
| Network | | GSM / HSPA / LTE |
| SIM card | | Dual SIM (Nano-SIM, dual stand-by) |
| 5G Network | 1, 3, 28, 41, 77, 78 SA/NSA | |
| Bluetooth | 5.1, A2DP, LE, aptX HD | 4.2, A2DP, LE |
| Edge | | Yes |
| CDMA | CDMA 800 | |
| GPRS | | Yes |
| GPS | Yes, with A-GPS, GLONASS, BDS, GALILEO | Yes, with A-GPS |
| Speed | HSPA 42.2/5.76 Mbps, LTE-A, 5G | HSPA 42.2/5.76 Mbps, LTE-A (2CA) Cat6 300/50 Mbps |
| NFC | No | |
| USB | USB Type-C 2.0, USB On-The-Go | microUSB 2.0, USB On-The-Go |
| Technology | GSM / CDMA / HSPA / CDMA2000 / LTE / 5G | |
| WLAN | Wi-Fi 802.11 a/b/g/n/ac/6, dual-band, Wi-Fi Direct, hotspot | |
| Camera | vivo Y31s 5G | Oppo A3s |
| Main camera | | 13 MP, Dual |
| Specs | | 13 MP, f/2.2, AF
-2 MP, f/2.4, depth sensor |
| Features | | LED flash, HDR, panorama |
| Video | | 1080p@30fps |
| Selfie camera | | 8 MP, Single |
| Multimedia | vivo Y31s 5G | Oppo A3s |
| Loudspeaker | Yes | |
| 3.5 mm Jack | Yes | Yes |
| Radio | No | FM radio |
| Design | vivo Y31s 5G | Oppo A3s |
| Colors | Red, Gray, Aurora | Red, Dark Purple |
| Dimensions | 164.2 x 75.4 x 8.4 mm (6.46 x 2.97 x 0.33 in) | 156.2 x 75.6 x 8.2 mm |
| Weight | 185.5 g (6.56 oz) | 168 g |
| SIM | Dual SIM (Nano-SIM, dual stand-by) | |
| Battery | vivo Y31s 5G | Oppo A3s |
| Type | Li-Po 5000 mAh, non-removable | |
| Charging | Fast charging 18W | |
| Battery capacity | | 4230 mAh, Non-removable Li-Ion |
| Features | vivo Y31s 5G | Oppo A3s |
| Sensors | Fingerprint (side-mounted), accelerometer, proximity, compass | |
| Other | vivo Y31s 5G | Oppo A3s |
| Release date | | 2018, July |
| Sensors | | Accelerometer, proximity, compass |
