Simply it display feeds of any user but one thing to remember you can display public posts or feeds on your website only..
Some remarkable feature of Google Plus Activity 1 ) It's simple 2 ) Very easy to use. 3 ) Documentation Available with images 4 ) Responsive 5 ) Easily customizable.
To find your google plus id follow the below steps..
Go to your profile or the ones you like to display on sidebar https plus google com +google.
The numeric numbers are your Google Plus User ID..
To do that first click on the project you have just created.
Click on API & Auth find Google+ Api and set it On.
Select Browser key domain name if want the domain name you will set the key will only accessible from that domain..
Copy API Key and paste in to your Joomla module field name API Key.
Browse the code, check out SVN repository, or subscribe to the development log by RSS...
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