What device do I need to run Zwift through to get rider shadows?
To get rider shadows you’d need a PC or Mac with a dedicated GPU that gets the medium graphics profile or higher. Minimum spec is an NVIDIA GT 1030 or MX-150 (laptop) or GTX 560, GTX 660, GTX 750 Ti, GTX 950 or AMD RX 460 (but best to avoid AMD for Zwift). The Apple M1 chip had rider shadows when it first came out, then it got downgraded to fake blob shadows around about December 2020. I have no idea why. It’s very capable and will do 1440 res with the high profile for everything else. Battery life maybe.
shadows were glitched out like crazy recently so you really aren’t missing much