 <p>Include <code>email</code> in your list of OAuth scopes. Then, in the token you get back, there will be a <code>hd</code> attribute if it's a Google Apps account. If the <code>hd</code> attribute is not present, its' a consumer account. Be aware that it's possible to create a consumer account that has an address of something other than @gmail.com or @googlemail.com. For example, I can create a consumer account with the address jsmith@yahoo.com or jsmith@acme.com as long as I can get email to those addresses. Thus the need to check <code>hd</code> instead of depending on the domain name.</p>