Android/iOS: Google announced today that it iss updating the notification system for Google+. The rollout begins with Android and the web, with iOS to follow.
The new system brings synced notifications across all of your devices, which can clear up a lot of clutter. The notification tray also separates read items from unread, so you can tell when you're up to speed and what you have left. Additionally, the app will now include the officially-sanctioned navigation drawer to be more consistent with other Google apps.
The update is rolling out over the course of today to the Android app and the web. If you don't have the Android app, you can get it at the source link below.