Here is what I got new in this update :
• Pin posts in your Collections
• New design of Communities
• Performance improvements and bug fixes
• Improved navigation and overall experience for screen reader users
They made it more fast and fluid with this update. New version of Google+ update bumps up to v7.9.0. Apk File size is 22.6MB. This update will support Android 4.4+ devices. Some Major changes I found in this update is Community get some minor design changes, New navigations feature.
You can download this update APK file from below link:
Google+ APK v7.9.0