When the Steam Link app hits smartphones later this month, most of users Steam Library of games will be playable on their phone in 4K resolution at 60 frames-per-second, but only when they are connected to their home network — and its best if that network is 5 GHz, not 2.4 GHz networks, Valve told Variety.

The idea for the free Android and iOS app came about as a natural extension of Valve’s Steam In-Home Streaming technology which allowed users to play computer games on a television using a small Steam Link peripheral. The peripheral, though, won’t be required to use this new Steam Link app. “We’ve had lots of customers asking for the ability to stream elsewhere in their home besides their TV,” Valve’s Sam Lantinga, lead on the technology, told Variety. “The bathroom has come up a lot, oddly enough.”

Lanting said that the app is using the same Steam In-Home Streaming technology used in the Steam Link. “Under the hood we’re doing real-time encoding of H.264 video, sending it over a custom low latency network protocol, and decompressing it on the client,” he said. “In general you can play any game that works with a Steam Controller. There is a small amount of latency that will affect competitive multiplayer games, and the larger screen of a tablet is preferred for games with lots of text or small details.”

He added that at launch the app will support any iOS device running iOS 10 or newer, and any Apple TV running tvOS 10.3 or newer. On the Android side, Valve plans to initially release in beta so it can do more exhaustive testing. At the start of the beta, the app will support Android 5.0 or newer.

The quality bar for the stream is 1080p at 60 FPS with good quality for most scenes, he said. “If you have a powerful rig, wired network, and very good client device, it’s possible to stream at 4K 60 FPS. You can go into the advanced streaming settings and tune streaming resolution and bitrate for the best experience in your setup.”

The app does tinker with the view a bit, adding black bars on the edges to deal with aspect ratio differences and the video is scaled to handle different screen sizes. Players will also be able to use two finger pinch and pan gestures to zoom in as needed on the screen.

The app is slated to launch the week of May 21 and will feature support for the Steam Controller, MFI controllers, and more across both platforms. The Steam Controller will not work outside of the app, on mobile phones.

Later this summer, Valve says, the Steam Video app will debut, allowing users to enjoy the thousands of movies and shows available on Steam directly via their Android and iOS devices over Wi-Fi or LTE both in offline and streaming modes.

The Steam Link initially launched in 2015 as a piece of hardware that could be used to stream your Steam content from a computer to a TV set wirelessly. The small device released alongside the Steam Machine, Valve’s take on the computer-meets-console that could deliver all of Steam’s content to your TV through what looked like a cable box.