| Hardware and OS | Ulefone Armor 21 | |
| Operating system | Android 13 | |
| Processor | Mediatek MT8781 Helio G99 | |
| GPU | Mali-G57 MC2 | |
| RAM | 8 GB | |
| Internal Storage | 256 GB | |
| Memory Card Slot | microSDXC (dedicated slot) | |
| User Interface | Yes | |
| Display | Ulefone Armor 21 | other phones |
| Type | IPS LCD | |
| Size | 6.58 inches | |
| Resolution | 1080 x 2408 pixels | |
| Colors | 16M Colors | |
| Pixel Density | 401 ppi | |
| Touchscreen | Yes | |
| Features | 120Hz | |
| Connectivity | Ulefone Armor 21 | other phones |
| 4G Network | 1, 2, 3, 4, 5, 7, 8, 12, 17, 19, 20, 28, 34, 38, 39, 40, 41, 66 | |
| 5G Network | No | |
| Wi-Fi | Wi-Fi 802.11 a/b/g/n/ac, dual-band | |
| GPS | GPS, GLONASS, GALILEO, BDS | |
| NFC | Yes | |
| USB | Type-C 2.0 | |
| Speed | HSPA, LTE | |
| SIM | Nano SIM | |
| Dual SIM | Yes | |
| Wireless Charging | No | |
| Camera | Ulefone Armor 21 | other phones |
| Main camera | 64 MP (wide), 24 MP (night vision) | |
| Features | Yes | |
| Image | 2160p | |
| Selfie camera | 16 MP (wide) | |
| Multimedia | Ulefone Armor 21 | other phones |
| Loudspeaker | Yes | |
| Handsfree | Yes | |
| Radio | Yes | |
| Video Playback | Yes | |
| Video Out | Yes | |
| Ring Tones | Yes | |
| 3.5 mm Jack | Yes | |
| Design | Ulefone Armor 21 | other phones |
| Dimensions | 176 x 81.6 x 18.1 mm | |
| Waterproof | IP68/IP69K dust/water resistant (up to 1.5m for 30 min) | |
| Weight | 400 grams | |
| Battery | Ulefone Armor 21 | other phones |
| Capacity | Li-Po 9600 mAh, 33W wired | |
| Placement | Non-removable | |
| Other | Ulefone Armor 21 | other phones |
| Sensors | Side-mounted fingerprint, accelerometer, proximity, compass, gyro, barometer, | |
