Samsung Galaxy S21 Ultra (SM-G998W 256GB) vs Samsung Galaxy A15 (SM-A155M/DSN 128GB/4GB)
Side by side comparison between Samsung Galaxy S21 Ultra vs Samsung Galaxy A15 phones, differences, pros, cons and full specifications. What's the better?
,
6.8"
AMOLED
AMOLED
1440x3200
108
MP
MP
40mp
12GB
RAM
RAM
Octa-core
5000
mAh
mAh
(Non removable)
vs
6.5"
AMOLED
AMOLED
1080x2340
50
MP
MP
13mp
4GB
RAM
RAM
Octa-core
5000
mAh
mAh
(Non removable)
What's the better phone? Samsung Galaxy S21 Ultra (SM-G998W 256GB)
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!
30 Advantages 
5 Advantages | 21 Common items in both devices |
| Dynamic AMOLED / Super AMOLED |
| 16 million |
| LED flash |
| PDAF: phase detection autofocus on both cameras / Autofocus |
| HDR photo/video on both cameras / HDR photo on both cameras |
| f/1.8 (aperture) |
| Android 14 |
| +14 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 | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Model | Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) |
| Other model names | Galaxy S21 Ultra 5G (SM-G998W) | Galaxy A15 4G LTE SM-A155M/Dual-SIM NFC |
| Country or region available |  Canada |       (Latin America), Bolivia, Brazil, Chile, Paraguay, Uruguay |
| Brand | Samsung | Samsung |
| Release date | 1/29/2021, Announced: 1/14/2021 | 12/16/2023, Announced: 12/11/2023 |
| Depth | 8.9 millimeters (0.35 inches) | 8.4 millimeters (0.33 inches) |
| Size (width x height) | 75.6 x 165.1 millimeters (2.98 x 6.5 in) | 76.8 x 160.1 millimeters (3.02 x 6.3 in) |
| Weight | 227 grams (7.95 ounces) | 200 grams (7 ounces) |
| Build, materials | Aluminum frame, glass front/back | Plastic body, glass front |
| Protection against water and others | IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant | Not supported |
📲 Display | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Display type | Dynamic AMOLED | Super AMOLED |
| Screen size | 6.8" inches | 6.5" inches |
| Screen-to-body ratio | ~89.4% (screen-to-body ratio) | ~84.3% (screen-to-body ratio) |
| Display resolution | 1440x3200 pixels (20:9) | 1080x2340 pixels (19.5:9) |
| Touchscreen | Capacitive Multitouch 10-points | Capacitive Multitouch |
| Pixel density (dot pitch) | 516 PPI | 396 PPI |
| Colors | 16 million | 16 million |
| Scratch-resistant glass | Gorilla Glass Victus | Not supported |
| Refresh rate | 120Hz | 90Hz |
| Display features | 1500nits[peak] HDR10+ Always-On Display | 800nits[peak] |
🤖 Operating System | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| System version | Android 11 | Android 14 |
| Firmware update | Android 14 | feature not registered |
| User Interface | One UI 3.1 / 4.1 / 5.1 / 6.0 | One UI 6.1 |
⚙️ Processor | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Chipset | 64bit: Qualcomm Snapdragon 888 (SM8350) (5nm) | 64bit: MediaTek Helio G99 (6nm) |
| CPU | Octa-core, 3 processors: 1x 2.84GHz Kryo 680 (Single-core) 3x 2.42GHz Kryo 680 (Triple-core) 4x 1.8GHz Kryo 680 (Quad-core) | Octa-core, 2 processors: 2x 2.2GHz ARM Cortex-A76 (Dual-core) 6x 2GHz ARM Cortex-A55 (Hexa-core) |
| GPU graphical controller | Qualcomm Adreno 660 (840MHz) | ARM Mali-G57 MC2 |
| Performance (benchmark) | AnTuTu: 681099 (v8), 809165 (v9) Geekbench: 3539 (v5.2) GFXBench: 54fps (ES 3.1 onscreen) | AnTuTu: 317085 (v9), 375321 (v10) Geekbench: 1928 (v5), 1936 (v6) |
💽 Memory and storage | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| RAM memory | 12GB LPDDR5 | 4GB LPDDR4X |
| Internal storage | 256GB (220GB available) UFS 3.1 | 128GB (108GB available) eMMC 5.1 |
| External storage | Not supported | Until 1TB microSD, microSDXC (hybrid slot/shares the same SIM-2 slot) |
📶 Mobile networks | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Dual-SIM | Dual-SIM Standby - Call active on one sim card | Dual-SIM Standby - Call active on one sim card (hybrid slot/shares the same microSD slot) |
| SIM card | 1 slot (Single-SIM) nano-SIM (4FF) + e-SIM | 2 slots (Dual-SIM) nano-SIM (4FF) |
| Maximum Download / Upload | 5000/1920 Mbps | 300/150 Mbps |
| Network technology | 2G, 3G, 4G, 5G | 2G, 3G, 4G |
| 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 Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 18, 19, 20, 25, 29, 30, 66, 71) TD-LTE (38, 39, 40, 41, 46) VoLTE | LTE Cat7 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 26, 28, 66) TD-LTE (38, 40, 41) VoLTE |
| Primary 5G network | SA/NSA/Sub6 (2, 41, 66, 71) | Not supported |
| 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 |
| 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 Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 18, 19, 20, 25, 29, 30, 66, 71) TD-LTE (38, 39, 40, 41, 46) VoLTE | LTE Cat7 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 26, 28, 66) TD-LTE (38, 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 |
📷 Camera | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Back camera (main camera) | (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 | (triple camera) 50 megapixels 5MP ultrawide f/2.2 2MP macro f/2.4 |
| Main camera resolution | 12000x9000 pixels | 8160x6120 pixels |
| Video recording (primary) | 8K UHD (7680x4320) 24 fps | Full HD (1920x1080) 30 fps |
| Flash | LED flash | LED flash |
| Focal aperture | f/1.8 (aperture) | f/1.8 (aperture) |
| Focal length | 26mm lens | feature not registered |
| Sensor size | 1/1.33" inches | feature not registered |
| Pixel size | 1.8µm pixel | feature not registered |
| Autofocus | PDAF: phase detection autofocus on both cameras | Autofocus |
| Touch focus | Supported | Supported |
| Image stabilization | OIS: Optical stabilization | EIS: Digital stabilization |
| Zoom | Digital and optical zoom | Only digital zoom |
| Face/smile detection | Face detection, Smile detection | Face detection, Smile detection |
| BSI sensor | Supported | Supported |
| HDR | HDR photo/video on both cameras | HDR photo on both cameras |
| Camera extras | 4K@60fps 1080p@240fps 720p@960fps | 1080p@30fps 720p@120fps (slow motion) |
📸 Front camera | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Front camera (secondary) | 40 megapixels | 13 megapixels |
| Front camera resolution | 7296x5472 pixels | 4128x3096 pixels |
| Video recording (secondary) | 4K UHD (3840x2160) | Full HD (1920x1080) |
| Front flash | Not supported | Not supported |
| Focal aperture | f/2.2 (aperture) | f/2.0 (aperture) |
| Focal length | 26mm lens | feature not registered |
| Sensor size | 1/2.8" inches | feature not registered |
| Pixel size | 0.7µm pixel | feature not registered |
🔉 Sound and multimedia | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Loudspeaker | Stereo sound 32-bit/384kHz Dolby Atmos Tuned by AKG | Mono sound (not stereo) |
| Active noise cancellation | 2 microphones or more | 2 microphones or more |
| Radio | FM | FM (RDS) |
| 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 | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| USB | USB 3.2 Type-C, USB OTG On-The-Go | USB 2.0 Type-C, USB OTG On-The-Go |
| Audio output | Type-C reversible connector | 3.5mm jack |
| TV output | USB Type-C (reversible) | USB Type-C (reversible) |
| Bluetooth | 5.2 + A2DP/LE | 5.3 + 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 [wifi5] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot |
| DLNA | Supported | Not supported |
| GPS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou, QZSS |
| NFC | Supported | Supported |
| Infrared port | Not supported | Not supported |
🧭 Sensors | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Sensors | Accelerometer Ambient light sensor Barometer Compass Face unlock Fingerprint sensor (under display) Gesture Gyroscope Hall effect Proximity sensor UWB (Ultra Wideband) | Accelerometer Ambient light sensor Compass Face unlock Fingerprint sensor (side-mounted) Virtual proximity sensor |
| Vibrating alert | Supported | Supported |
🔋 Battery | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| Battery type | LiPo: li-ion polymer (Non removable) | LiPo: li-ion polymer (Non removable) |
| Battery capacity | 5000 mAh | 5000 mAh |
| Charger, watts | 25W Wired fast charging USB Power Delivery 3.0 | 25W Wired fast charging |
| Inductive / wireless charging | 15W Qi wireless charging (Qi/PMA) 4.5W Reverse wireless charging | Not supported |
| Talk time autonomy | feature not registered | 51 hours (2.1 days) |
| Standby | feature not registered | feature not registered |
➕ Other features | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| 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: Phantom Black, Silver, Titanium, Navy, Brown • Samsung Pay (Visa, MasterCard) • Samsung DeX • Stylus pen support | • Colors: Brave Black, Optimistic Blue, Magical Blue, Personality Yellow |
☢️ Radiation rate | ||
| Galaxy S21 Ultra (SM-G998W 256GB) | Galaxy A15 (SM-A155M/DSN 128GB/4GB) | |
| SAR 1.6W/kg (USA, Mexico, etc.) | 1.12W/kg (head), 1.25W/kg (body) | feature not registered |
| SAR 2W/kg (Europe, UK, etc.) | feature not registered | feature not registered |