SDK and Rest API: Google+ Communities support

[GoogleCodeExporter]

Describe in detail the new feature you would like to see added
-> What new capabilities would you like to see added to the API?

I have added several google+ communities for my android application (e.g. 
MyApp) e.g. I've created two communities as follows:

- MyApp
- MyApp Support

Each community has various categories or 'channels' on which content is posted.

I would like to be able to 

1) register my android app user from within my android application to a given 
community programmatically 

e.g. I would add a menu item or button to myApp called 'Join MyApp Community' 
and internally have the gplus client do the registration

2) execute an intent from MyApp that launches Google+ and immediately shows a 
given Google+ Community in question so the user can view and post as desired.

3) execute an intent from my app to post to a given community/category combo

Describe your use case, or some example use cases, for this feature
->Why do you want this feature, and how might it be valuable not just to
your application, but to many developers?

I have a 'business' around an android application game that is published in 
google play (MyApp=Bot World AI Chat)

I have added several google+ communities

- MyApp
- MyApp Support

I would like to integrate my game with these (basic) communities so users can 
post/view/discuss game related topics.

These topics would correspond to google community 'categories'.  Example 
categories:

Latest Release Info & Feedback
Game successes
Game issues 
New feature requests
....

Better integration between Android and Google+ Communities would help drive 
social media buzz.

Tx.

Original issue reported on code.google.com by elisebot...@gmail.com on 5 Jan 2014 at 2:41

[GoogleCodeExporter]

Original comment by t...@google.com on 6 Jun 2014 at 9:36

[GoogleCodeExporter]

Original comment by t...@google.com on 18 Sep 2014 at 2:20

[GoogleCodeExporter]

I would like to add a user to a community, dedicated to users of our 
application.
Users already log into our application using Google OAuth, so extra permission 
to join specific community would be best.
Alternative would be for our service to send requests to new users of 
application if they want to join the community.

Original comment by m...@adria-team.com on 14 Oct 2014 at 1:58