Group Play has been an option on Samsung Galaxy S4 and upwards.

Group Play lets users pair up multiple devices and share pictures, documents and music among them in real time. So you could have 8 Samsung S5 phones all acting as one loudspeaker. I’m trying to imagine how good that would sound!

Anyway, my S5 received an update to the Group Play app to v3. But v3 also added Group Camcorder. Group Camcorder lets you pair up to 4 devices and capture videos from each device’s camera, then lets the host device edit and merge the best shot sequences, basically incorporating the camera output from all connected devices.

Now if I can find anyone with a S5 I will try this and let you know how I get on.