Why can't I log in to the Salesforce1 Android app with a dev account?

OK, thanks to @ThomasTaylor, I found out that the answer turned out to be Connected Apps settings under Setup/Administration Setup/Manage Apps/Connected Apps. I'd never been to this page to my knowledge and I'm the only one who uses this SFDC account, so I'm not sure if this was a default setting or if was changed somehow.

The Permitted Users for Salesforce1/Chatter for Android was set to "Admin approved users are pre-authorized" while every other app was set to "All users may self-authorize". I changed to it to "All users may self-authorize" and was able to log in again.

I'm not sure how the permitted users settings was changed for this. It's odd that I was able to log in at all, albeit briefly. It makes me think that something programatically changed it on me.

The errors that Salesforce1 gives are not that good. If it had told me I didn't have permission when I tried to log in, that would have been more helpful.