Sony will be releasing a PlayStation Communities app from tomorrow for Android and iOS devices, bringing the PS4 feature to mobile. The app will allow you to do everything that the Communities feature does on the PS4, such as posting comments and joining groups that interest you. There will be a notifications system that alerts you when someone responds to one of your posts, or tags you in one.
The Communities app will sync up with the other PlayStation apps, with those receiving updates tomorrow too.
Source: PS Blog