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Updated January 10, 2024·
If a superior camera is a priority, the Samsung Galaxy S21 Ultra has a higher overall camera quality and more versatile camera system with telephoto and periscope lenses offering impressive zoom capabilities. However, if you prefer a lighter device with slightly longer battery life, and if spending less is important, the OnePlus 9 could be the right choice for you. Both phones have powerful processors, but the Galaxy S21 Ultra boasts a larger screen with a higher resolution, making it better for media consumption. Keep in mind that both have different ecosystems, as the OnePlus uses OxygenOS and Samsung employs One UI, both based on Android. If expandable storage through an SD card is crucial, neither of these phones supports it. Give Feedback
this description is based on the product variant with some specs and product variant with some specs. At the time of writing, the variant with some specs cost some dollars and the variant with some specs cost some dollars.
Advantages of the OnePlus 9
- The OnePlus 9 has no clear advantages over the Samsung Galaxy S21 Ultra.
Advantages of the Samsung Galaxy S21 Ultra
- Good for taking photos
- Good for recording videos
- Very good display quality
- Good performance
Key differences
Overall Camera Quality
7.0
7.8
The Samsung Galaxy S21 Ultra and OnePlus 9 both have good overall camera quality, though the Samsung Galaxy S21 Ultra has somewhat better overall camera quality.
The Samsung Galaxy S21 Ultra offers a superior camera experience with better photos software, dynamic range, camera versatility, and particularly excels in low light conditions in both photos and videos compared to the OnePlus 9. Additionally, the Galaxy S21 Ultra boasts higher selfie quality, reflecting its edge in these areas, making it a compelling choice for users prioritizing camera performance.
Photo Quality
6.7
7.8
The Samsung Galaxy S21 Ultra takes good photos, while the OnePlus 9 takes only fair photos.
The Samsung Galaxy S21 Ultra delivers better photo quality due to its superior photos software experience and dynamic range, along with enhanced low light performance and camera versatility when compared to the OnePlus 9. Despite both phones having good selfie scores, the Galaxy S21 Ultra's overall camera capabilities are more advanced, offering a more robust photography experience.
Video Quality
5.9
7.1
The Samsung Galaxy S21 Ultra takes good videos, while the OnePlus 9 takes poor videos.
The OnePlus 9 takes fair videos due to its fair performance in video stabilization, dynamic range, and low light performance, and poor microphone quality, while the Samsung Galaxy S21 Ultra provides good videos with its very good stabilization, dynamic range, low light performance, and good mic quality.
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Key similarities
Battery
6.9 Hours
6.7 Hours
The OnePlus 9 has 6.9 hours of battery life. The Samsung Galaxy S21 Ultra has 6.7 hours of battery life.
Screen Size
The OnePlus 9 has a screen size of 6.55 inches and the Samsung Galaxy S21 Ultra is 6.8 inches.
Cost
$399
$423
$200
$300
$400
$500
$600
$700
The OnePlus 9 has a price of $399 and the Samsung Galaxy S21 Ultra costs $423.
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How the OnePlus 9 and the Samsung Galaxy S21 Ultra compare to other phones
Spec Comparison
 |  | |
| OnePlus 9 | Samsung Galaxy S21 Ultra |
GENERAL | |||
|---|---|---|---|
| Price | |||
$399 | $423 | ||
Brand | |||
Brand | OnePlus | Samsung | |
Operating System | |||
Operating System | Android | Android | |
Release Date | |||
Release Date | March 26, 2021 | January 29, 2021 | |
SCREEN | |||
|---|---|---|---|
Screen Size | |||
Screen Size | 6.55" | 6.8" | |
Resolution | |||
Resolution | 2400 x 1080 | 3200 x 1440 | |
Variable refresh rate | |||
Variable refresh rate | No | Yes | |
Pixels Per Inch | |||
Pixels Per Inch | 402 | 515 | |
Display Type | |||
Display Type | OLED | OLED | |
INTERNAL | |||
|---|---|---|---|
Processor | |||
Processor | SD888 | SD888 | |
Internal Storage | |||
Internal Storage | 128 GB | 128 GB | |
RAM | |||
RAM | 8 GB | 12 GB | |
CAMERA | |||
|---|---|---|---|
Overall Camera Quality Score | |||
Overall Camera Quality Score | 7/10 | 7.9/10 | |
Photos Score | |||
Photos Score | 6.8/10 | 7.8/10 | |
Videos Score | |||
Videos Score | 5.9/10 | 7.1/10 | |
Rear Cameras | |||
Rear Cameras | Main, Ultrawide | Main, Ultrawide, Telephoto, Super Telephoto | |
Main Camera | |||
Main Camera | 48 megapixels | 108 megapixels + OIS | |
BATTERY | |||
|---|---|---|---|
Battery Life | |||
Battery Life | 6.9 Hours | 6.7 Hours | |
Battery Capacity | |||
Battery Capacity | 4500 mAh | 5000 mAh | |
Wireless Charging | |||
Wireless Charging | Yes | Yes | |
Wireless charging Speed | |||
Wireless charging Speed | 15 W | 15 W | |
Reverse wireless charging | |||
Reverse wireless charging | No | Yes (4.5 watts) | |
PHYSICAL | |||
|---|---|---|---|
Size | |||
Size | 6.29" x 2.92" | 6.5" x 2.98" | |
Weight | |||
Weight | 6.77 oz | 8.01 oz | |
Back Material | |||
Back Material | Glass | Glass | |
Stereo Speakers | |||
Stereo Speakers | No | No | |
CONNECTIVITY | |||
|---|---|---|---|
Dual SIM | |||
Dual SIM | No | Yes | |
Bluetooth Version | |||
Bluetooth Version | 5.2 | 5.2 | |
A2DP | |||
A2DP | Yes | Yes | |
WiFi Version | |||
WiFi Version | 6 | 6e | |
NFC | |||
NFC | Yes | Yes | |
US 5G Bands | |||
US 5G Bands | (SA/NSA/Sub6)1, 2, 3, 5, 7, 8, 20, 25, 28, 38, 40, 41, 48, 66, 71, 77, 78 | (SA/NSA/Sub6/mmWave)2, 5, 25, 41, 66, 71, 260, 261 (SA/NSA/Sub6)1, 3, 5, 7, 8, 20, 28, 38, 40, 41, 66, 77, 78 | |
OTHER FEATURES | |||
|---|---|---|---|
Biometric unlock | |||
Biometric unlock | Face unlock, Fingerprint sensor: Under Display | Face unlock, Fingerprint sensor: Under Display | |
Unlockable Bootloader | |||
Unlockable Bootloader | Yes | No | |
Color | |||
Color | Astral Black, Arctic Sky, Winter Mist | Phantom Black, Phantom Silver, Phantom Navy, Phantom Titanium | |
Stock Android | |||
Stock Android | No | No | |
SD Card | |||
SD Card | No | No | |
Shopping
OnePlus 9
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Dig into reviews and images
TechRadar
David Lumb | April 2021
"If you’re hunting for the best Android camera phone at this price, and one that doesn’t skimp on specs the OnePlus 9 is worth considering. Courtesy of a partnership with Hasselblad, the cameras offer better color correction, and both regular and ultra-wide photos look great. The OnePlus 9’s battery fully charges in under 30 minutes over a cable, and in 45 minutes using wireless charging. If you hate waiting for hours to charge your phone, you'll love the OnePlus 9."
Samsung Galaxy S21 Ultra
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Dig into reviews and images
Android Authority
David Imel | January 2023
"The Galaxy S21 Ultra is a killer combo of great design, blazing-fast performance, a wonderful display, long-lasting battery life, and one of the most versatile camera systems you can get in a smartphone today."
Get a great deal on the OnePlus 9 or the Samsung Galaxy S21 Ultra
About OnePlus
OnePlus, established in 2013, is a smartphone brand that first became known for providing flagship-like devices, at a fraction of the cost compared to more expensive Android competitors. OnePlus focuses on creating smartphones with powerful hardware at reasonable prices. They also bring hardware features normally not seen in other Android phones sold in the US, such as their ultra-fast “Warp Charge” and the beloved “Alert Slider”.
About Samsung
Samsung is one of the most recognizable names in the smartphone industry, standing as the undisputed best-selling brand of Android smartphones in the United States for many years now. Samsung is known for offering a variety of smartphones in all available price points, as well as for implementing cutting-edge technology and innovative features in their flagship devices, ones that often shape the market going forward. The company offers its own unique spin on Android, called One UI, which focuses on offering a multitude of features and is heavily customizable, according to user preference.
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Why trust us
This information was produced and vetted by the PerfectRec phones team. We are a product research and recommendation organization that meticulously reviews and evaluates the latest phone information and makes it digestible for you.
By the numbers
68
Phones evaluated
7,820
Phones stats compiled
8
Proprietary Phones ratings developed
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Recommendations made
81,430
Consumer hours saved
About the phone team
Joe Golden, Ph.D
CEO and Phones Editor
Joe is an entrepreneur and lifelong electronics enthusiast with a Ph.D in Economics from the University of Michigan.
Jason Lew
Staff Expert & Software Engineer
Jason is a staff expert and software engineer that has been making laptop recommendations for 7 years and moderates one of the largest laptop subreddits.
Chandradeep Chowdhury
Staff Expert & Software Engineer
Chandradeep is a staff expert and software engineer and expert in televisions and monitors. He’s been making monitor recommendations for ten years.
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Seth is a US-based product expert focusing on smartphones and he is a moderator of one of the largest smartphone subreddits. His tailored recommendations have helped him earn over 87k comment karma, putting him in the top 1% of Redditors.
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Phones Expert
Efthimis is a Greece-based product expert focusing on smartphones. He has been recommending phones for 4 years and his recommendations on Reddit have earned him over 35k karma.
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