This Free App Lets You Play Your Steam Games From Your Phone

Part of the beauty of Steam libraries is that they aren't tied to a single device, and many Steam users enjoy their collections with PCs and Steam Decks alike. But what about when you want to game away from your computer and don't have a Steam Deck (or if your Steam Deck is just out of battery)? That's when playing Steam games on your phone comes in, and there's a free app that lets you do just that: Moonlight Game Streaming.

Moonlight is an open-source app that lets you play your PC games on your phone, as well as a host of other supported client devices. Since your experience with the app will largely depend on the limitations of your internet connection, you'll want to ensure your network is strong enough to handle remote play. We recommend wiring your internet connection with a good Cat6 Ethernet cable to get the best data transfer speeds — and therefore the lowest latency — as you possibly can. If your hardware of choice can support it, Moonlight even lets you stream in 4K at 120fps and HDR using a piece of open-source software called Sunshine.

Previously, Moonlight used Nvidia GeForce Experience as a stream host, but GeForce has since been phased out and replaced with the new Nvidia App, which doesn't support GameStream. GameStream was Nvidia's proprietary protocol designed to stream high-performance PC games from a computer. It used Nvidia GPUs to get the job done, and it was designed for use with the Nvidia Shield streaming box. But eventually, Nvidia retired this streaming tech, which led the community to create Sunshine as a replacement stream host. Conversely, Moonlight is the streaming software used on receiving client devices — like cell phones — to display games streamed via Sunshine. Using these tools, you can access specific applications designed for streaming, such as Steam's Big Picture Mode.

Setting up Moonlight Game Streaming on your phone is fairly simple. First, you'll have to install Sunshine on your host device, which should be your PC. You can install it directly from LizardByte's GitHub repository or through Lizardbyte's official website. Your phone will then require the Moonlight app, which you can find on both Google Play and the App Store as "Moonlight Game Streaming." The Android app should be published by Cameron Gutman, while the iOS app will list Diego Waxemberg as the developer. You can also navigate to the official Moonlight website's "Client downloads" tab in the main navigation menu to access app downloads for various platforms, including all major desktop and mobile operating systems, Amazon Fire OS, and even Nintendo Switch Homebrew.

Once you have Sunshine and Moonlight installed on your PC and phone respectively, you can begin setting them up. Moonlight's setup guide on Github provides detailed instructions for how to configure your software under various circumstances. One of the main considerations is that both your host and client devices need to be connected to the exact same network. The whole process shouldn't take long — all you're really doing is configuring your PC as a Sunshine server, then connecting it to the phone that's mirroring your game via Moonlight. The official documentation also strongly recommends creating a Sunshine account when you first pair your host device with the mobile app; otherwise, anyone who happens to gain access to your Sunshine configuration could use your computer remotely by adding their own client devices to it.

Even with a hardwired internet connection on your host PC and a 5GHz router — if you have a 2.4GHz router, you'll likely experience significant latency — you'll still want to tweak a few settings to optimize your experience and ensure your host PC is up to snuff for stable server performance. On Windows, under Control Panel > Hardware and Sound > Power Options, setting your PC to high-performance mode instead of balanced mode or energy-saving mode may help reduce stuttering during streaming. You can also follow guidance in the "Advanced Usage" section of the Sunshine documentation to adjust your Sunshine configuration file as needed.

You may also have to configure the controller input values to match your gamepad. If you want to use special controllers like steering wheels, you'll have to download a separate software tool, such as VirtualHere, for it to work. If you're using a phone to game, however, you're likely also using an Android or iOS-compatible gamepad; you generally shouldn't have any issues using a Bluetooth-enabled game controller with the Moonlight app.

Don't forget to adjust the video resolution, frame rate, and bitrate values in the Moonlight app — but before selecting 4K video at 120fps, check whether your device's chipset supports those settings. This is important because the Moonlight app is what decodes the video stream from your PC. If you try running a game at a resolution that your phone can't handle, you'll experience poor framerates, regardless of how powerful your host machine and network connection are. If you're using an Android and aren't sure about which video settings to apply, you can test different frame pacing options, such as "Prefer lowest latency" or "Prefer smoothest video," to see which one delivers the best experience for you.