It's been a year after Communities launched on Playstation 4 in the System Software 3.0 update. To celebrate this, Sony launched the feature as a mobile app for iOS and Android devices.
The new mobile Communities App functions exactly the same as the PS4 version, allowing users to create and join groups, as well as interact with them at any time.
The app makes it easy by helping players find groups based on games they've been playing, finding groups friends are a part of, and join midway in a conversation and become a part of it. It also gives optional push notifications to keep players involved and reminded of their discussions, so they never miss out. It even interacts with the existing Playstation and Playstation Messages apps! No longer requiring switching to different ones to get where you want.
Source: Playstation Blog