Isn't this.... pointless? I already log in once on my device, click 'save password', and I never type it in again. So "removing the login" is a solution for a problem that doesn't exist.
If anything, this post only highlights how we need more security on our mobile devices.
We also need more convenience, though, especially for low-security things like discussion forums and blog comments where the choice is often between a lousy password and a lousy password reset scheme. Your solution only works well with a convenient (no extra steps beyond "save my password") and ubiquitous (works with all major platforms, browsers, and applications) password synchronization system.
If anything, this post only highlights how we need more security on our mobile devices.