[simon_weber]

Google's authentication schemes can be incredibly confusing, and they're something I've had to deal with while building an unofficial client to Google Music [0].

Here are two things worth knowing (that are somewhat covered by the article):

* aside from OAuth, any method of client auth is basically equivalent to SSO (ie, your entire Google account). As noted in the article, this includes app-specific passwords

* SSO is not meant for programmatic access. If you want code to have access to SSO credentials, it's easiest to use some other auth service, and then "upgrade" to SSO (the linked blog post describes one way of doing this) [1]

[0] https://github.com/simon-weber/Unofficial-Google-Music-API

[1] http://nelenkov.blogspot.com/2012/11/sso-using-account-manag...