DroidDeck brings the SteamOS experience to Android: Valve's Steam client in Big Picture on your Adreno handheld, with Windows games through Valve's ARM64 Proton.

Note: DroidDeck does not have a stand-alone website. Do not click on any download links from websites claiming to be the DroidDeck team.

Requirements and install

Use Android 9 or newer on a supported Adreno device (730 or newer, or 8xx). Adreno 6xx is experimental: DirectX 11 uses DXVK 2 and may run, and DirectX 12 games can still crash. Mali, Xclipse, PowerVR, and Adreno 710 are unsupported. No root is required. Allow about 3 GB for the runtime and 1.1 GB more for the desktop and emulators. Install the APK from Releases, install the Linux runtime, then press Play and sign in. Steam downloads on first launch. Install Desktop & apps to use the desktop and emulators. The Store installs Linux apps and games from Flathub (ARM64 builds) with Flatpak; with additional options to install Appimages and set up scripts. Stores (Setup › Stores › "Show Stores in the rail") signs in to GOG, Epic Games and Amazon Games and downloads games into the Games storage. Epic keeps its direct API install path. Opening Epic Stores prepares Epic’s official Linux launcher preview. When installed, Epic games launched from DroidDeck use that client, and games installed in the client are imported into DroidDeck’s library and shortcuts. The x86-64 client runs through FEX on ARM and DroidDeck retains its Proton hooks; this preview and ARM setup are outside Epic’s listed Linux support. The cog on a store’s chip row sets its opening tab and download speed tier.

On Android 14 and newer, before Steam launches, you must turn on Disable child process restrictions in Developer options. If this option is not available in developer settings (Android 12 and 13 devices), first launch of Steam will present a "Fix it for me" button, which will help automate the setup process.

Smart glasses

Use Setup → Smart glasses for app-wide virtual-screen settings across DroidDeck menus, launchers, desktop sessions, and games. Supported VITURE, RayNeo, XREAL, and Rokid connections provide 3DoF; Luma Ultra adds optional experimental 6DoF and stereo-assisted hand/Joy-Con tracking. Model support and SDK requirements differ: see the smart-glasses support matrix for supported devices, controls, setup, and limitations.

Community

Join the DroidDeck Discord for help, Preview builds, and device reports. Bug reports go in its #bug-reports forum; attach the zip from Share logs (Setup, or the session drawer) so the logs come with it.

Build

Run tools/build_local.sh with Docker, Java 17, the Android SDK/NDK, Rust through rustup, GitHub CLI, Python 3, and zstd installed. It prepares the same native libraries, pinned components and audio sinks as CI, then checks the APK's assets, JNI exports and dependencies. The APK is at app/build/outputs/apk/release/app-release.apk. Set DROIDDECK_PA13_SOURCE_DIR to an existing PulseAudio 13.0 source directory to skip downloading it. Set DROIDDECK_SIGNING_ENV to a signing environment file to install over a release build; relative keystore paths resolve beside that file. To install on an attached device, run tools/deploy_local.sh.

After preparation, ordinary ./gradlew :app:assembleRelease builds can reuse the verified inputs. If native sources, component pins or staged files change, packaging stops with instructions to rerun the helper. Generated audio stays under app/build/; the tracked base bundle is never modified. ./gradlew -PskipRust=true :app:testDebugUnitTest needs no native preparation. For an APK without store engines, use DROIDDECK_SKIP_RUST=1 tools/build_local.sh; it omits cached engine libraries too.

For the prepared Windows checkout, run ./tools/run_windows.ps1 (optionally with -Serial <adb-serial>), or select DroidDeck XR in Android Studio and run the app module on the connected phone. Machine-specific options live in the ignored local.properties: droiddeck.python selects a Python executable, droiddeck.skipRust=true omits the optional store download engines, and droiddeck.debugApplicationIdSuffix=.xr installs DroidDeck XR Dev alongside the signed release. The development app has its own runtime and Steam login. The local Java selection is in .gradle/config.properties.

python tools/prepare_windows_runtime.py restores this checkout's audited runtime inputs from the pinned CI APK, three locally rebuilt preload libraries, and the checksum-pinned Gamescope archive in build/windows-setup/. Start Docker Desktop's Linux engine first: preparation now rebuilds DroidDeck's ARM64 VR driver and Vulkan layer from current source and runs their native regression tests. The compiler image is built automatically on first use. Vulkan headers come from the NDK beside --llvm-strip, or from an explicit --vk-include <NDK-sysroot-include> directory.

To reuse that build, pass --rebuilt-vr build/windows-setup/vr. Preparation verifies its vr-build.json against the current Git revision, source files, Vulkan headers, output checksums, and ARM64 architecture; missing or stale builds fail instead of falling back to the donor's VR libraries. The script checks the actual donor CI merge tree, still rejects unrelated unaudited runtime changes, and records component provenance in app/build/windows-runtime-provenance.json. Preserve these ignored preparation files when rebuilding locally; clean removes the prepared assets and their verification manifest.

Run the helper and preload regression suite with bash tools/test_local.sh. On macOS it runs in Linux through Docker, matching the helpers' runtime and CI instead of compiling Linux preloads against macOS headers.

Limits

Compatibility and performance vary by device; hardware validation is limited. Desktop compositing uses software rendering. Firefox sandboxing is reduced under proot. Logs are kept app-private (files/logs/, the last 30 sessions); Share logs packs the newest session, with the stores and tool logs, into one scrubbed zip.

Credits and licence

GPL-3.0. Runtime, shim, input, and controller work build on WinNative and Bannerlator (maxjivi05). Epic Games and GOG support build on Phobos’s adaptation of Legendary and gogdl, respectively. The registry entries a GOG game's install script (goggame-<id>.script) sets are read the way Heroic Games Launcher's GOG setup (GPL-3.0) reads them. LSFG frame generation is from the work of Camille LaVey and the Eden emulator project, following lsfg-vk, ported to WinNative and DroidDeck by @maxjivi05; it needs your own copy of Lossless Scaling and ships none of its shaders. x86 AppImages, and any whose own runtime cannot unpack them, are unpacked with uruntime by VHSgunzo (MIT), shipped unmodified with its licence, which also starts the arm64 emulator AppImages whose own runtime cannot run its extractor on Android. The Steam client's audio goes through @The412Banner's DirectAudio PulseAudio sink (LGPL-2.1-or-later), built from tools/directaudio/sink with its request size kept to its ring so clients are not asked to queue 100 ms ahead. mmap ring-buffer controller input was developed by ribbit384 (WinNative #345). Why the x86-64 Steam client refused the arm64 client's sign-in was checked by reading Steam's saved token with the ConnectCache format from deadlock-api-ingest. x86 programs that link OpenSSL 3 under FEX use the copy in the Steam Linux Runtime 4.0 platform. Hooks written with WriteProcessMemory into code FEX has translated go through /proc/<pid>/mem again when the kernel refuses process_vm_writev, as Wine's server/ptrace.c wrote them before Wine 11. x86 Linux games under FEX get the same /etc/asound.conf that pressure-vessel writes into the Steam Linux Runtime, so ALSA plays through PulseAudio. Games render with Mesa Turnip's own per-render-pass choice between tile memory and system memory, while the Steam client keeps TU_DEBUG=sysmem; FEX's code disk cache was checked in its source and is already on through Proton. The proot fast path picks the guest name of a host file bound under several names in the order PRoot's path/binding.c (GPL-2.0-or-later) sorts its bindings, so links and /proc/self/fd read back as they do through proot. The session's PipeWire (MIT) opens its sockets with the per-socket access settings documented in its module-access.c, and WirePlumber (MIT) keeps those clients at full permissions through its access.rules. Wine write watches use the userfaultfd support in Proton's dlls/ntdll/unix/virtual.c (LGPL-2.1-or-later): libblsession gives it the arm64 syscall number and answers its PAGEMAP_SCAN from /proc/self/pagemap where Android refuses the ioctl. Wine on arm64 sets a thread's full context by raising SIGUSR2 from syscall_dispatcher_return_slowpath in Wine's dlls/ntdll/unix/signal_arm64.c (LGPL-2.1-or-later); libblsession runs that handler in place on a frame laid out as the Linux kernel's arch/arm64/kernel/signal.c builds it and returns through rt_sigreturn, so proot does not stop the thread for it. Wine's process list reads each process's memory counters from /proc/<pid>/status in fill_vm_counters (Wine dlls/ntdll/unix/process.c, LGPL-2.1-or-later), so libblsession gives those reads the kernel's file instead of a copy with TracerPid cleared. droiddeck-ntsync is checked against the object, wait and error semantics documented for the Linux ntsync driver in Documentation/userspace-api/ntsync.rst (GPL-2.0). See LICENSE. Steam and Proton belong to Valve Corporation; this project is not affiliated with Valve.

XR glasses support builds on WinNative's VITURE glasses work. VITURE protocol details were checked against XRLinuxDriver by @wheaney, including the VITURE protocol header it ships, ar-drivers-rs by @badicsalex and the go-macos/iokit VITURE package; the optional VITURE SDK belongs to VITURE and is not included. RayNeo support adapts @informalTechCode's RayNeo-Air-Series-3DoF-Scaffold (Apache-2.0) and references @verncat's RayNeo-Air-3S-Pro-OpenVR (MIT) and Monado (BSL-1.0); see docs/third-party/rayneo. XREAL 1S support references XRLinuxDriver and xrealOneDeviceKit by @wheaney, xreal_one_driver by @rohitsangwan01 (MIT) and xr-tools by @0xcaff. Rokid support follows the Rokid protocol notes in ar-drivers-rs and @badicsalex's Void Computing write-ups, and Monado's Rokid driver. The REDMAGIC glasses-display findings draw on @mekhontsev's MagicDesk investigation and @Coding-BR's decompiled Nubia kernel. VITURE, RayNeo, XREAL, Rokid and REDMAGIC are trademarks of their owners; this project is not affiliated with them.

Joy-Con VR controllers port the arm model of Google's Google VR SDK for Unity (Apache-2.0), adapt the hand skeleton of Valve's OpenVR handskeletonsimulation sample (BSD-3-Clause), which follows Moshi Turner's hand simulation in Monado, and use the Index controller offsets from Monado's vive_poses.c (BSL-1.0). Joy-Con behaviour was researched in Linux's hid-nintendo driver by Daniel J. Ogorchock, @dekuNukem's Nintendo_Switch_Reverse_Engineering, SDL and the Android Open Source Project, and checked against ALVR, OpenComposite, PSMoveSteamVRBridge, @F8LEFT's JoyConVr, @krnelpan1c's Daydream-Controller-SteamVR, @yoyobuae's joyconvr, Moonlight and Dolphin; see docs/third-party/joycon. Nintendo Switch and Joy-Con are trademarks of Nintendo; this project is not affiliated with Nintendo.

Camera hand tracking runs Google's MediaPipe Tasks Vision library with its Pose Landmarker (Lite) model, BlazePose GHUM 3D, and its Hand Landmarker model (all Apache-2.0), on frames from AndroidX CameraX (Apache-2.0); MediaPipe's usage reports are switched off. The design was checked against @F8LEFT's JoyConVr camera app (MIT), and the short Joy-Con movements follow the accelerometer mode of the Google VR SDK for Unity's arm model, Eric Foxlin's zero-velocity updates and Frosio, Pedersini and Borghese's accelerometer autocalibration, and the camera and Joy-Con are joined by a Kalman filter (R. E. Kalman, 1960). Bare camera hands take their gestures after ALVR's hand_gestures.rs (MIT) and Meta Quest's menu pinch, with distances checked on photos from the HaGRID gesture set (CC BY-SA 4.0, not included), fit the palm with Horn's quaternion method (1987) and smooth it with the 1€ filter (Casiez, Roussel and Vogel, 2012); the white glove model follows Valve's OpenVR render model reference and Index controller poses, is meshed with surface nets (Gibson, 1998; Mikola Lysenko) and blends and shades it with Inigo Quilez's smooth minimum and distance-field ambient occlusion, porting his polygon distance (MIT); see docs/third-party/handtracking.

The Store installs and runs apps with Flatpak (LGPL-2.1). Its sandbox goes through DroidDeck's own bubblewrap shim, which follows how Flatpak hands bwrap its environment. Chromium and Electron apps from Flathub start their browser processes through zypak by @refi64 (BSD-3-Clause); its source was read to see that it always spawns them through Flatpak's spawn portal, which is why DroidDeck starts them directly without Chromium's sandbox instead.