One of the PlayStation 4's coolest announced features is Remote Play, the service that will allow you to use WiFi to mirror and play PS4 games on your Vita. Today, Sony revealed some specifics about how that Remote Play will work—and they caution that it might not work so well when your Vita is on a different WiFi network than your PS4.
.. You can only use Remote Play via WiFi—not 3G—and your PS4 will have to be turned on for the feature to work.
Sony also recommends not traveling too far if you want to get Remote Play working properly:
When will Remote Play work best?
Remote Play will work best when the PS Vita system is located within the same WiFi network where PS4 is connected. We also recommend that PS4 be connected to the local area network via an Ethernet cable, that a router suitable for gaming be used and that the PS Vita system be within close proximity of the WiFi access point so that the connection is free of interference.
Can Remote Play work outside the user's home network?
We strongly recommend that Remote Play be used within the same WiFi network where PS4 is connected. Remote Play may or may not work over a wide area network. For Remote Play to function over a wide area network, a robust and stable WiFi connection and broadband Internet connection is required, and the local area network where PS4 is connected must be configured to permit the PS Vita system to access PS4.
"But wait a minute!" you might be thinking. "I thought Sony was advertising the ability to play PS4 games on the go!"
So, if you go out of town, and even if you login to Wi-Fi, you can't play PS4 games. But you can on your other couch.