The Google+ app has gone through more UI revisions than Android itself, and the latest one is starting to roll out now. Version 6.8 of Google+ is starting to show up in the Play Store, and of course, we've got the APK below if you don't want to wait. Be aware, installing this APK won't immediately kick you over to the new design. It looks like this is a server-side switch that's only active for some users.
The new Google+ has a more consistent design across platforms. In the Android app, you'll notice we finally have a proper slide-out navigation menu. There's also a tab bar that pops up at the bottom of the feed with quick access to home, collections, communities, and notifications. The settings are also arranged differently, and there's access to the G+ activity log from the app. It's just a little different everywhere, but still recognizable as G+.
Several AP staffers have gotten the new UI upon installing the app, but your mileage may vary. Feel free to install and see if you're a winner. If not, it shouldn't be long. Things might change a bit when the rollout is complete, though. See below for the old UI.
Force new UI
You should be able to force the app to switch over to the new UI by deleting the G+ app data in settings.
- APK Mirror