iDeck brings Steam and Windows games to the iPhone, but sideloading is still required

An open-source project uses translation and compatibility layers to run Steam and games such as Tomb Raider locally on recent iPhones, though users still need JIT-enabled sideloading and technical know-how.

iDeck is an open-source project that tries to do something most iPhone users would normally expect to require a gaming PC: run Valve’s Steam client, open a library, and launch Windows games locally on the handset rather than streaming from elsewhere. In the demo described by KOCPC, an iPhone opens the app, logs in to Steam, shows the Big Picture interface and starts the 2013 reboot of “Tomb Raider” with touch-friendly on-screen controls arranged around the display.

The software sits on top of Madeira, the underlying runtime that handles the heavy lifting. According to the project description, Madeira combines FEX-Emu for x86 and x86-64 translation to ARM64, Wine 11.4 in ARM64EC form to provide the Windows environment, DXMT for Direct3D 9, 10 and 11 rendering on Metal, and madeira-d3d12 for Direct3D 12 support using Apple’s Metal Shader Converter. Because iOS does not allow one app to launch another process in the usual way, Madeira also works around the platform by running Wine’s server logic as threads inside a single process.

That base layer brings several features of its own. The project says it supports Steam login, downloading through a Madeira Dock interface, Steam Cloud synchronisation with conflict handling and backup creation, Bluetooth controller input through XInput, virtual touch controls and direct keyboard, mouse and trackpad input. iDeck’s main addition is to place Valve’s official Steam Big Picture interface on top, so users remain inside Steam’s own account system, authentication flow and game licensing checks rather than a separate launcher.

KOCPC notes that Madeira also includes a Windows desktop session, which means some non-game Windows applications may be able to open as well. Control options include a physical gamepad, direct touch input and a virtual on-screen pad, although the latter is still being verified. A floating iDeck button can be dragged anywhere on screen to summon the keyboard, show control mappings, change layout settings, open the Steam menu or request a clean exit from a game.

The project is still not a simple install-and-play download. The public release is a source snapshot rather than a finished build, and it does not include a compiled runtime or ready-made IPA. Users must obtain Steam’s CEF client through legitimate channels, and the project warns against copying someone else’s authentication cache. JIT support is also required, which means the app depends on sideloading and debugging-related pairing tools rather than the App Store. Madeira requires iOS 26 or later, and the current demo hardware is the latest iPhone Pro class, which helps explain why the showcase title was an older game that is more likely to run well than a recent, demanding release.

The idea is not entirely new. DroidDeck, the Android project that inspired iDeck, has already attracted a large following as an open-source attempt to bring a Steam-like handheld experience to mobile devices, and its official iOS pages make clear that the Android project is not available for iPhone or iPad. In that context, iDeck is better understood as part of a wider experiment in making phones behave more like pocket gaming PCs, while also drawing a clear line between local execution and cloud streaming. It is not SteamOS on iPhone, and it is not an ARM-native iOS port of the game itself; it is a Windows game running through a compatibility layer on Apple hardware, with all the limits that implies.