Google+ allows you to organize your friends and contacts into smart groups known as Circles. If you would like to quickly access your circles in the Google+ app, you can create a shortcut to your circle streams in the navigation drawer of the app. Here are the instructions on how to access your Circle Streams in the Google+ app (Android and iOS).
Add Circle Streams to the Navigation Drawer on Google+ App
Open the Google+ app and then tap on the Menu key > Settings > Display circle streams. Tick the Show your circle streams in navigation drawer checkbox and exit the Settings menu:
Tap on the Menu > Circles streams to view your circles: