When you say "OAuth", what exactly do you mean? It looks like this is really just a tool for associating email addresses with SSH keys.

This is an interesting concept, but it smells a bit like a solution in search of a problem. Perhaps it will feel more useful to me once there are two or three SSH apps that I want to access. Even then, I would suggest that prospective SSH app developers just lean on github's public SSH keys instead, as basically all developers will have a github account and this reduces your (already high, relative to webapp) startup friction.