| Hardware and OS | Xiaomi Mi Mix 3 | Oppo A3s |
| Operating system | Android 9.0 (Pie); MIUI 10 | Android 8.1 (Oreo); ColorOS 5.1 |
| Processor | Octa-core (4x2.8 GHz Kryo 385 Gold & 4x1.7 GHz Kryo 385 Silver) | Octa-core 1.8 GHz Cortex-A53 |
| Chipset | Qualcomm SDM845 Snapdragon 845 (10 nm) | Qualcomm SDM450 Snapdragon 450 (14 nm) |
| GPU | Adreno 630 | Adreno 506 |
| Internal memory | 256 GB, 8/10 GB RAM128 GB, 6/8 GB RAM | 16 GB, 2 GB RAM |
| External memory | No | microSD, up to 256 GB (dedicated slot) |
| Display | Xiaomi Mi Mix 3 | Oppo A3s |
| Type | Super AMOLED | IPS LCD |
| Size | 6.39" inc | 6.2" inc |
| Resolution | 1080 x 2340 px | 720 x 1520 px |
| Touchscreen | capacitive touchscreen | capacitive touchscreen |
| Protection | Corning Gorilla Glass 5 | |
| Screen-to-Body Ratio | 85.0% | 81.2% |
| Display area | 100.2 cm2 | 95.9 cm2 |
| Display aspect ratio | 19.5:9 (height:width) | 19:9 (height:width) |
| Pixel Density | 403 PPI | 271 PPI |
| Colors | 16M | 16M |
| Other | HDR | |
| Connectivity | Xiaomi Mi Mix 3 | 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 800 / 850 / 900 / 1700(AWS) / 1800 / 1900 / 2100 - Global | HSDPA 850 / 900 / 2100 |
| 4G Network | LTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 7(2600), 8(900), 12(700), 13(700), 17(700), 18(800), 19(800), 20(800), 25(1900), 26(850), 28(700), 29(700), 30(2300), 34(2000), 38(2600), 39(1900), 40(2300), 41(2500), 66(1700/2100) - Global | LTE |
| Wi-Fi | Wi-Fi 802.11 a/b/g/n/ac, dual-band, WiFi Direct, hotspot | Wi-Fi 802.11 b/g/n, WiFi Direct, hotspot |
| Network | GSM / CDMA / HSPA / EVDO / LTE | GSM / HSPA / LTE |
| SIM card | Dual SIM (Nano-SIM, dual stand-by) | Dual SIM (Nano-SIM, dual stand-by) |
| Bluetooth | 5.0, A2DP, aptX HD, LE | 4.2, A2DP, LE |
| Edge | Yes | Yes |
| GPRS | Yes | Yes |
| GPS | Yes, with dual-band A-GPS, GLONASS, BDS, GALILEO, QZSS | Yes, with A-GPS |
| Speed | HSPA, LTE | HSPA 42.2/5.76 Mbps, LTE-A (2CA) Cat6 300/50 Mbps |
| USB | Type-C 1.0 reversible connector | microUSB 2.0, USB On-The-Go |
| NFC | Yes | |
| Camera | Xiaomi Mi Mix 3 | Oppo A3s |
| Main camera | 12 MP, Dual | 13 MP, Dual |
| Specs | 12 MP (wide), f/1.8, 1/2.55', 1.4µm, Dual Pixel PDAF, 4-axis OIS
-12 MP (telephoto), 1/3.4', 1.0µm | 13 MP, f/2.2, AF
-2 MP, f/2.4, depth sensor |
| Features | LED flash, HDR, panorama | LED flash, HDR, panorama |
| Video | 2160p@30/60fps, 1080p@30/60fps, 1080p@960fps | 1080p@30fps |
| Selfie camera | 24 MP, Dual | 8 MP, Single |
| Multimedia | Xiaomi Mi Mix 3 | Oppo A3s |
| 3.5 mm Jack | No | Yes |
| Radio | No | FM radio |
| Design | Xiaomi Mi Mix 3 | Oppo A3s |
| Colors | Jade Green, Sapphire Blue, Onyx Black, Forbidden City Blue (10 GB only) | Red, Dark Purple |
| Dimensions | 157.9 x 74.7 x 8.5 mm | 156.2 x 75.6 x 8.2 mm |
| Weight | 218 g | 168 g |
| Body build | Front glass, aluminum frame (7000 series), ceramic back | |
| Battery | Xiaomi Mi Mix 3 | Oppo A3s |
| Battery capacity | 3200 mAh, Non-removable Li-Ion | 4230 mAh, Non-removable Li-Ion |
| Other | Xiaomi Mi Mix 3 | Oppo A3s |
| Release date | 2018, October | 2018, July |
| Sensors | Fingerprint (rear-mounted), accelerometer, gyro, proximity, compass | Accelerometer, proximity, compass |
