Xiaomi Poco X4 GT (128GB) vs Samsung Galaxy S21 Ultra (SM-G998B 512GB)
Side by side comparison between Xiaomi Poco X4 GT vs Samsung Galaxy S21 Ultra phones, differences, pros, cons and full specifications. What's the better?
,
6.6"
IPS
IPS
1080x2460
64
MP
MP
16mp
8GB
RAM
RAM
Octa-core
5080
mAh
mAh
(Non removable)
vs
6.8"
AMOLED
AMOLED
1440x3200
108
MP
MP
40mp
16GB
RAM
RAM
Octa-core
5000
mAh
mAh
(Non removable)
What's the better phone? Samsung Galaxy S21 Ultra (SM-G998B 512GB)
The phonemore's choice is much more technical than personal. Therefore, you shouldn't only consider this. Our goal is to help you, but what's important to us may not be important to you. You decide which one is the best! Comment!
7 Advantages 
25 Advantages | 24 Common items in both devices |
| UFS 3.1 |
| 8.9 millimeters (0.35 inches) |
| Dolby Vision/HDR10 / HDR10+ |
| 16 million |
| LED flash |
| PDAF: phase detection autofocus / PDAF: phase detection autofocus on both cameras |
| HDR photo on both cameras / HDR photo/video on both cameras |
| +17 specs and more in the table below |
Check the comparison table below for more items that are not evaluated in comparison score above.
Highlight differences Clear highlight📱 Model features | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Model | Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) |
| Other model names | POCO X4 GT 5G (8GB RAM) | Galaxy S21 Ultra 5G (SM-G998B Single-SIM) |
| Country or region available |  (Global, International) |  Australia |
| Brand | Xiaomi | Samsung |
| Release date | 6/27/2022, Announced: 6/23/2022 | 1/29/2021, Announced: 1/14/2021 |
| Depth | 8.9 millimeters (0.35 inches) | 8.9 millimeters (0.35 inches) |
| Size (width x height) | 74.29 x 163.64 millimeters (2.92 x 6.44 in) | 75.6 x 165.1 millimeters (2.98 x 6.5 in) |
| Weight | 200 grams (7 ounces) | 227 grams (7.95 ounces) |
| Build, materials | Plastic body, glass front | Aluminum frame, glass front/back |
| Protection against water and others | Not supported | IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant |
📲 Display | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Display type | TFT IPS LCD | Dynamic AMOLED |
| Screen size | 6.6" inches | 6.8" inches |
| Screen-to-body ratio | ~85.1% (screen-to-body ratio) | ~89.4% (screen-to-body ratio) |
| Display resolution | 1080x2460 pixels (20.5:9) | 1440x3200 pixels (20:9) |
| Touchscreen | Capacitive Multitouch | Capacitive Multitouch 10-points |
| Pixel density (dot pitch) | 407 PPI | 516 PPI |
| Colors | 16 million | 16 million |
| Scratch-resistant glass | Gorilla Glass 5 | Gorilla Glass Victus |
| Refresh rate | 144Hz | 120Hz |
| Display features | 500nits[typ] Dolby Vision/HDR10 DCI-P3 | 1500nits[peak] HDR10+ Always-On Display |
🤖 Operating System | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| System version | Android 12 | Android 11 |
| Firmware update | feature not registered | Android 14 |
| User Interface | MIUI 13 | One UI 3.1 / 4.1 / 5.1 / 6.0 |
⚙️ Processor | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Chipset | 64bit: MediaTek Dimensity 8100 (5nm) | 64bit: Samsung Exynos 2100 (5nm) |
| CPU | Octa-core, 2 processors: 4x 2.85GHz ARM Cortex-A78 (Quad-core) 4x 2GHz ARM Cortex-A55 (Quad-core) | Octa-core, 3 processors: 1x 2.9GHz ARM Cortex-X1 (Single-core) 3x 2.8GHz ARM Cortex-A78 (Triple-core) 4x 2.2GHz ARM Cortex-A55 (Quad-core) |
| GPU graphical controller | ARM Mali-G610 MC6 | ARM Mali-G78 MP14 (854MHz) |
| Performance (benchmark) | feature not registered | AnTuTu: 657150 (v8), 727634 (v9) Geekbench: 3457 (v5.2) GFXBench: 51fps (ES 3.1 onscreen) |
💽 Memory and storage | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| RAM memory | 8GB LPDDR5 | 16GB LPDDR5 |
| Internal storage | 128GB (101GB available) UFS 3.1 | 512GB (457GB available) UFS 3.1 |
| External storage | Not supported | Not supported |
📶 Mobile networks | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Dual-SIM | Dual-SIM Standby - Call active on one sim card | Dual-SIM Standby - Call active on one sim card |
| SIM card | 2 slots (Dual-SIM) nano-SIM (4FF) | 1 slot (Single-SIM) nano-SIM (4FF) + e-SIM |
| Maximum Download / Upload | 2000/1024 Mbps | 5000/1920 Mbps |
| Network technology | 2G, 3G, 4G, 5G | 2G, 3G, 4G, 5G |
| Frequency, bands | Expand band details Collapse details | |
| GSM MHz band | Quad-Band 850/900/1800/1900 | Quad-Band 850/900/1800/1900 |
| Primary 2G network | GSM 850/900/1800/1900 | GSM 850/900/1800/1900 |
| Primary 3G network | UMTS 850/900/1700/1900/2100 | UMTS 850/900/1700/1900/2100 |
| Primary 4G network | LTE Cat13 (1, 2, 3, 4, 5, 7, 8, 20, 28, 38, 40, 41) TD-LTE (38, 40, 41) VoLTE | LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 32, 66) TD-LTE (38, 39, 40, 41) VoLTE |
| Primary 5G network | Global version: SA/NSA (1, 3, 5, 7, 8, 20, 28, 38, 40, 41, 77, 78) India version: SA/NSA (1, 3, 5, 8, 28, 38, 40, 41, 77, 78) | SA/NSA/Sub6 (1, 3, 5, 7, 8, 20, 28, 38, 40, 41, 66, 77, 78) |
| Primary data network | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA |
| Secondary 2G network | GSM 850/900/1800/1900 | GSM 850/900/1800/1900 |
| Secondary 3G network | UMTS 850/900/1700/1900/2100 | UMTS 850/900/1700/1900/2100 |
| Secondary 4G network | LTE Cat13 (1, 2, 3, 4, 5, 7, 8, 20, 28, 38, 40, 41) TD-LTE (38, 40, 41) VoLTE | LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 32, 66) TD-LTE (38, 39, 40, 41) VoLTE |
| Secondary data network | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA |
📷 Camera | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Back camera (main camera) | (triple camera) 64 megapixels 8MP ultrawide f/2.2120°1/4"1.12µm 2MP macro f/2.41.75µm | (quad camera) 108 megapixels 10MP periscope telephoto f/4.9240mm1/3.24"1.22µmPDAFOIS10x-optical-zoom 10MP telephoto f/2.470mm1/3.24"1.22µmPDAFOIS3x-optical-zoom 12MP ultrawide f/2.213mm1/2.55"1.4µmPDAFSuper-Steady-video |
| Main camera resolution | 10120x6328 pixels | 12000x9000 pixels |
| Video recording (primary) | 4K UHD (3840x2160) 30 fps | 8K UHD (7680x4320) 24 fps |
| Flash | LED flash | LED flash |
| Focal aperture | f/1.9 (aperture) | f/1.8 (aperture) |
| Focal length | feature not registered | 26mm lens |
| Sensor size | 1/1.72" inches | 1/1.33" inches |
| Pixel size | 0.8µm pixel | 1.8µm pixel |
| Autofocus | PDAF: phase detection autofocus | PDAF: phase detection autofocus on both cameras |
| Touch focus | Supported | Supported |
| Image stabilization | EIS: Digital stabilization | OIS: Optical stabilization |
| Zoom | Only digital zoom | Digital and optical zoom |
| Face/smile detection | Face detection, Smile detection | Face detection, Smile detection |
| BSI sensor | Supported | Supported |
| HDR | HDR photo on both cameras | HDR photo/video on both cameras |
| Camera extras | 1080p@60fps | 4K@60fps 1080p@240fps 720p@960fps |
📸 Front camera | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Front camera (secondary) | 16 megapixels | 40 megapixels |
| Front camera resolution | 4608x3456 pixels | 7296x5472 pixels |
| Video recording (secondary) | Full HD (1920x1080) | 4K UHD (3840x2160) |
| Front flash | Not supported | Not supported |
| Focal aperture | f/2.5 (aperture) | f/2.2 (aperture) |
| Focal length | feature not registered | 26mm lens |
| Sensor size | 1/3.06" inches | 1/2.8" inches |
| Pixel size | 1µm pixel | 0.7µm pixel |
🔉 Sound and multimedia | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Loudspeaker | Stereo sound with dual speakers 24-bit/192kHz Dolby Atmos | Stereo sound 32-bit/384kHz Dolby Atmos Tuned by AKG |
| Active noise cancellation | 2 microphones or more | 2 microphones or more |
| Radio | Not supported | FM |
| TV | Not supported | Not supported |
| Video formats | MP4, H.265, H.264, H.263, XviD, MKV | MP4, H.265, H.264, H.263, XviD, MKV |
| Audio formats | MP3, WAV, WMA, eAAC+, FLAC | MP3, WAV, WMA, eAAC+, FLAC |
🔌 Connectivity | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| USB | USB 2.0 Type-C, USB OTG On-The-Go | USB 3.2 Type-C, USB OTG On-The-Go |
| Audio output | 3.5mm jack | Type-C reversible connector |
| TV output | USB Type-C (reversible) | USB Type-C (reversible) |
| Bluetooth | 5.3 + A2DP/LE | 5.2 + A2DP/LE |
| WiFi | 802.11 a/b/g/n/ac/ax [wifi6] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot | 802.11 a/b/g/n/ac/ax [wifi6] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot |
| DLNA | Not supported | Supported |
| GPS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou, QZSS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou |
| NFC | Supported | Supported |
| Infrared port | Supported | Not supported |
🧭 Sensors | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Sensors | Accelerometer Ambient light sensor Compass Face unlock Fingerprint sensor (side-mounted) Gyroscope Proximity sensor | Accelerometer Ambient light sensor Barometer Compass Face unlock Fingerprint sensor (under display) Gesture Gyroscope Hall effect Proximity sensor UWB (Ultra Wideband) |
| Vibrating alert | Supported | Supported |
🔋 Battery | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Battery type | LiPo: li-ion polymer (Non removable) | LiPo: li-ion polymer (Non removable) |
| Battery capacity | 5080 mAh | 5000 mAh |
| Charger, watts | 67W Wired fast charging Reverse charging by cable USB Power Delivery 3.0 | 25W Wired fast charging USB Power Delivery 3.0 |
| Inductive / wireless charging | Not supported | 15W Qi wireless charging (Qi/PMA) 4.5W Reverse wireless charging |
| Talk time autonomy | feature not registered | feature not registered |
| Standby | feature not registered | feature not registered |
➕ Other features | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| Call control | Voice dialing, Voice recorder, Voice commands | Voice dialing, Voice recorder, Voice commands |
| Messaging | SMS (T9), MMS, E-mail, Push mail | SMS (T9), MMS, E-mail, Push mail |
| Hands-free calling | Supported | Supported |
| Video calling | Supported | Supported |
| Ringtones | Polyphonic and customized | Polyphonic and customized |
| Web browser | HTML, XHTML, HTML5 | HTML, XHTML, HTML5 |
| Antenna | Internal antenna | Internal antenna |
| Qwerty physical keyboard | Not supported | Not supported |
| Miscellaneous | • Colors: Black, Blue, Silver • LiquidCool Technology 2.0 | • Colors: Phantom Black, Silver, Titanium, Navy, Brown • Samsung Pay (Visa, MasterCard) • Samsung DeX • Stylus pen support |
☢️ Radiation rate | ||
| Xiaomi Poco X4 GT (128GB) | Galaxy S21 Ultra (SM-G998B 512GB) | |
| SAR 1.6W/kg (USA, Mexico, etc.) | feature not registered | 0.24W/kg (head), 0.72W/kg (body) |
| SAR 2W/kg (Europe, UK, etc.) | feature not registered | 0.714W/kg (head), 1.58W/kg (body) |