Google is mass migrating for the login infrastructure and is reducing the number of old technologies. Check out this link for a review https://developers.google.com/+/web/api/rest/auth-migration
However, as a rule, there is no mention that they do not support Google+.
But for iOS, lately all their attention has gone to the Google Sign in SDK. (The Google+ sign in 1.7.1 was updated in 2014), but Google Sign was updated two weeks ago (September 15).
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