Why did you built your own login service when you could just use Dropbox authentication? I was about to try the app (just to give you feedback), but I will not sign up again, I'm afraid I will get a confirmation email.
Actually, the plan is to start with Dropbox and rolling out support for other cloud services, that's why.. Oh, there are no confirmation emails, I myself hate that.. Only reason email is at the register form is for `Forgot Password`, I've mentioned it in the about page.