Can you use both oauth2 and oauth1 ath the same time for authorization?

Question

As far as I understand, oauth2 is the way to go for Google Apps authentication (not openId anymore). However I am still a bit confused about authorization: can you use at the same time 3-legs oauth2 (for contacts, calendar and drive access...) and 2-legs oauth1 (for shared contacts, administration, licensing...)? Or do yo have to use exclusively 2-legs oauth1 (to give full control to domain administrators for example)? Thanks.

Answer 1

You can use Service Accounts in OAuth2 and acess APIs as domain administrator or impersonating a user.

Read more @ https://developers.google.com/accounts/docs/OAuth2ServiceAccount