This is great, thanks for posting it. I've had the same idea myself and started and abandoned this exact same project a few times. Same down to cutting the SDP up into multiple QR codes. I am glad to see this brought to life.

I am also surprised to see @nilknarf has done that in 2014! (As per their comment.) Don't know how I didn't come across his post during my research into this, but checking it now, someone in the comments posted a link to a patent which captures this idea.

http://www.freepatentsonline.com/20160021148.pdf

The patent must be invalid, because it's from 2016 and there is clearly prior art, but it kind of sucks, because it basically means polishing something like e.g. @phiresky has done with the remote pen just means if you succeed in bringing down the time to connect and make it something usable enough for users, you're opening yourself up to a claim if you decide to package it up into an app.