Best answer: UWB is short for ultra-wideband, a wireless technology that relies on radio waves to accurately gauge distance between objects. The S21+ and S21 Ultra have UWB and can be used as a virtual car key for select BMW models, and the tech is set to debut in Samsung's upcoming Tile-rivaling SmartTag+.
- The flagship to beat: Galaxy S21 Ultra ($1,200 at Samsung)
- The power you need: Galaxy S21+ ($1,000 at Samsung)
What is UWB in the Galaxy S21 series?
Think of ultra-wideband (UWB) as a turbocharged verison of Bluetooth. The Bluetooth LE (low energy) standard isn't ideal for location sensing because of the latency — which is usually over 3ms — but with UWB, that is brought down to under 1ms. UWB also has over three times the range of Bluetooth, and can transmit over 20 times the amount of data.
UWB has significant advantages over Bluetooth because it works at a higher frequency — the pulse-based technology uses spectrum from 3.1GHz to 10.6GHz. It also uses wider 500MHz channels to transmit data (Bluetooth is usually limited to 20MHz) and this allows the standard to send or receive a burst of data in a short amount of time.
UWB is an emerging standard, and right now there aren't many devices that leverage the tech. Auto manufacturers are embracing the standard as an easy way to unlock cars, with the likes of BMW, Audi, Ford, and others rolling out UWB compatibility to their latest models. So if you have a Galaxy S21+ or S21 Ultra, you can use your phone to unlock your car. The feature is being rolled out to select BMW models, but it should make its way to other manufacturers shortly.
Samsung has also introduced the SmartTag, which uses Bluetooth-based location positioning just like Tile trackers to help you find lost objects. It's set to introduce a UWB-based tracker in the coming months, dubbed SmartTag+.
What models in the Galaxy S21 series have UWB?
The Galaxy S21+ and S21 Ultra have UWB, with the regular S21 missing out on the feature. Samsung is positioning UWB as a differentiator on the S21+ and S21 Ultra, and with the imminent arrival of the SmartTag+, it is laying the groundwork for more use cases for the emerging wireless standard.
If you are interested in what UWB has to offer in the coming months and years, you'll want to get your hands on the Galaxy S21 Ultra or the S21+. The S21 Ultra, in particular, is one of the best Android phones you can buy right now, featuring the latest hardware and camera innovations in a gorgeous new design.
The flagship to beat
The flagship you deserve
The Galaxy S21 Ultra delivers incredible hardware in the form of a QHD+ AMOLED screen, the latest Qualcomm processor, 108MP primary camera with 10x zoom, global 5G, and a massive 5,000mAh battery that lasts well over a day.
The power you need
A great alternative
The Galaxy S21+ has the best features from the S21 Ultra in a more affordable package. The AMOLED panel has an FHD+ resolution, and you get a 12MP primary camera instead. But there's UWB out of the box, global 5G connectivity, and all the extras you're looking for.
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Harish Jonnalagadda is a Senior Editor overseeing Asia at Android Central. He leads the site's coverage of Chinese phone brands, contributing to reviews, features, and buying guides. He also writes about storage servers, audio products, and the semiconductor industry. Contact him on Twitter at @chunkynerd.