Netgear R7800 - Nighthawk X4S AC2600 Smart WiFi Router User Manual (en)

Use MyMedia to Play and Share Media Files 
 NETGEAR genie App
At the bottom, tap Options.
Slide the Allow play in the network slider to the right.
Devices on the network can now play media files using your iOS device.
Change the Media File Settings Using the Desktop genie 
You can change the following media file settings using the desktop genie app:
Video, audio, and image source folders on your computer that other devices can access.
The folder that files download to on your computer.
The amount of time images displays on your computer.
Change the Video File Settings Using the Desktop genie App
You can change the default video folder from which other devices can access video files and 
change the folder on your computer to which video files are download to.