About the second screen feature
The second screen feature lets you control your PS4™ system using a separate device. You can enter text on your device’s keyboard to be received by the PS4™ system. You can also view spectator comments on the second screen while you are broadcasting.
When playing games that support the second screen feature, you can also view game-related information on the device.
Use the second screen feature on any of the following devices:
- PS Vita systems
- Smartphones or other mobile devices
Not all games are compatible with the second screen feature.
Connecting from a PS Vita system
Use 
(PS4 Link) to connect from a PS Vita system. For details on how to connect, refer to the user’s guide for PS Vita system.
Connecting from a mobile device
Use 
(PS4 Second Screen) to connect to your PS4™ system from your smartphone or other mobile device. You can download (PS4 Second Screen) from Google Play™ or the App Store.
For details on how to connect, see "Mobile App Connection Settings".