I have compared them, and because BLE is a narrowband signal, it is highly susceptible to Non-Line-of-Sight (NLOS) conditions compared to UWB.
I also attended a prototype presentation by a large European silicon company. I noticed that even in their demo, BLE did not achieve 30 cm accuracy, but rather hovered around 1 m.
I have only tested PBR and RTT ranging with a simple Kalman Filter, so maybe someone has found a clever combination of these data sources (I hope).
It will allow things like secure entry (walk up to a door and it opens, be near your car and you can open it), finding your devices (lost keys, headphones, remotes, etc.), auto-unlocking for your laptop, and more.
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This is a really cool technology that is going to allow essentially indoor GPS. Imagine going to a mall, and you open a map on your phone, and it immediately knows where you are to under 1m error.
https://www.urbandictionary.com/define.php?term=sounding
> Sounding is the act of inserting a metal rod into your urethra.