Zuum Stellar P4 vs HMD XR21
| Type | Touch | Touch |
| Waterproofness & dust-resistance |  | IP68, IP69K |
| Dimensions | - | 168.00 x 78.58 x 10.45 mm |
| Weight | | 231.00 g |
| Display size | 6.50" | 6.49" |
| Display | Color / IPS TFT 16M colors 720 x 1600 px (6.50") 270 ppi | Color / IPS TFT 16M colors 120 Hz 1080 x 2400 px (6.49") 406 ppi |
| Display protection |   | Corning Gorilla Glass Buy screen protector
|
| Additional display | | |
| Protection of the secondary display | | |
| Standard battery | Li-Ion 4000 mAhBuy powerbank
| Li-Ion 4800 mAhBuy powerbank
|
| Quick battery charging | | USB Power Delivery 2.0 |
| Wireless battery charging | | |
| Internal memory | 64 GB | 128 GB |
| RAM memory | 3 GB | 6 GB |
| Memory cards |  microSD, microSDHC, microSDXC up to 128 GBBuy memory card | microSD, microSDHC, microSDXC up to 512 GBBuy memory card |
| Operating system | Android 11 | Android 13 |
| Processor | - | Qualcomm Snapdragon 695 SM6375 |
| Processor clock | 1600 MHz | 2200 MHz |
| GPU | - | Adreno 619 @840 MHz |
| Touchscreen | | |
| DualSIM | | |
| SIM cards standard | | DualSIM(eSIM, nanoSIM) |
| DualSIM mode | dual standby | dual standby |
| Hybrid DualSIM | | |
| Announced | | 2Q 2024 |
| Other names | - | - |
| GSM frequencies | 850 900 1800 1900 | 850 900 1800 1900 |
| UMTS | 850 900 1700 1900 2100 | 850 900 1700 1900 2100 |
| LTE standard | | FDD LTE: 2600, 2100, 1900, 1800, 1700, 1500, 900, 850, 800, 700 TDD LTE: 3700, 3500, 2600, 2500, 2300, 1900 |
| Standard 5G | | FDD 5G: 2600, 2100, 1900, 1800, 1700, 850, 700 TDD 5G: 3700, 3500 |
| CDMA | | |
| Standard TD-SCDMA | | |
| UMA | | |
CAMERAS - BACK
| First camera | | |
| Camera type | Standard | Standard |
| Photo sensor model | | OmniVision |
| Photo matrix | 13 Mpx | 64 Mpx |
| Sensor size | | 1/2 |
| Optical zoom | | |
| Flash | LED | LED |
| Dual-colour LED flash | | |
| Video resolution | | 1920x1080 px |
| Video formats | H.264, H.265, MPEG4 | H.263, H.264, MPEG4 |
| Additional | AF | AF, f/1.79 |
| Second camera | | |
| Camera type | Macro | Wide-angle |
| Photo matrix | 2 Mpx | 8 Mpx |
| Sensor size | | 1/4 |
| Pixel size | | 1,12 µm |
| Resolution | 1600x1200 px | 3264x2448 px |
| Optical zoom | | |
| Flash | LED | 3x LED |
| Dual-colour LED flash | | 1+2 |
| Video formats | H.264, H.265, MPEG4 | H.263, H.264, MPEG4 |
| Additional | FF | FF |
| Third camera | | |
| Camera type | Depth of field | nd |
| Photo matrix | 0.3 Mpx | nd |
| Resolution | 640x480 px | nd |
| Optical zoom | | nd |
| Flash | LED | nd |
| Dual-colour LED flash | | nd |
| Video formats | H.264, H.265, MPEG4 | nd |
| Additional | FF | nd |
CAMERAS - FRONT
| First camera | | |
| Camera type | Portrait | Portrait |
| Photo matrix | 5 Mpx | 16 Mpx |
| Optical zoom | | |
| Flash | | |
| Dual-colour LED flash | | |
| Video formats | H.264, H.265, MPEG4 | H.263, H.264, MPEG4 |
| Additional | FF | FF, f/2.45 |
SENSORS
| Accelerometer | | |
| Proximity | | |
| Light | | |
| Magnetometer | | |
| Gyroscope | | |
| Barometer | | |
| Altimeter | | |
| Gravity | | |
| Hall-effect | | |
| Iris scanner | | |
| Fingerprint scanner | | |
| Thermometer | | |
| Hygrometer | | |
Data transfer
| xHTML | | |
| WAP | v2.0 | v2.0 |
| HSCSD | | |
| HSDPA | 42.20 Mbit/s | 45.40 Mbit/s |
| HSUPA | 5.76 Mbit/s | 5.76 Mbit/s |
| HSPA | | |
| HSPA+ | | |
| LTE DL | - | 750.00 Mbit/s |
| LTE UP | 51.00 Mbit/s | 211.00 Mbit/s |
| WIMAX+ | | |
| GPRS | | |
| EDGE | | |
| Bluetooth | | v5.1 |
| A2DP Profile | | |
| HDMI | | |
| WiFi | v802.11 b/g/n | v802.11 a/b/g/n/ac/ax |
| WiFi frequencies | 2,4 GHz | 2,4 GHz; 5 GHz |
| WiFi Direct | | |
| WiFi Display | | |
| DLNA | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v2.0 Type-C | v2.0 Type-C |
| GPS | | |
| A-GPS | | |
| GLONASS | | |
| Beidou | | |
| Galileo | | |
| QZSS | | |
| NFC | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | T9 | T9 |
| Swype | | |
| e-mail client | POP3, IMAP4, SMTP | POP3, IMAP4, SMTP |
| Hardware QWERTY keyboard | | |
| RSS Reader | | |
Multimedia
| Radio | | |
| MP3 | | |
| Stereo speakers | | 2 |
| Audio Jack | 3.5 mm | 3.5 mm |
| HD Voice | | |
| Sound formats | AAC, AAC+, AMR, MID, WAV, eAAC+ | AAC, AAC+, AMR, MID, WAV, eAAC+ |
| Polyphony | | |
| Video ringtone | | |
| Ring composer | | |
| Games | | |
| Java | ART | ART |
| Videophone | | |
| DVB-H television | | |
| TV-Out | | |
PIM AND ADDITIONAL FUNCTIONS
| Watch | | |
| Stopwatch | | |
| Alarm | | |
| Calculator | | |
| Currency converter | | |
| Organizer | | |
| Calendar | | |
| Flight mode | | |
| SyncML | | |
| Data and fax | | |
| Screensaver | | |
| Themes | | |
| Interchangeable covers | | |
| Voice dial | | |
| Speakerphone | | |
| Recorder | | |
| Vibrations | | |