sidescreen

Side Screen is an open-source tool that turns an Android tablet into a genuine second display for a Mac. It targets a gap in macOS: Apple's Sidecar works only with iPads, while Android tablets can be used as extended screens through this project. Connection options - USB-C: cable connection with automatic adb-reverse port forwarding, described as the lowest-latency path. - Wireless: one-time QR pairing, after which the tablet remembers the Mac and reconnects automatically over WiFi. The auth token is generated locally on the Mac and can be reset to revoke access. 5 GHz WiFi is recommended. Display and streaming - Creates a true virtual display on macOS, so windows can be dragged to the tablet as an extension rather than a mirror. - Hardware-accelerated H.265 encoding on the Mac and decoding on Android, with an async pipeline; the README states frames are delivered in under 30 ms and mentions sub-16 ms pipeline latency on USB. - Touch input with touch prediction to compensate for network latency. - HiDPI (Retina) mode renders at 2x internally for sharper text and icons. - Gaming mode preset with 1 Gbps bitrate, low-latency encoding and 120 FPS. - Configurable resolution (720p up to 8K, presets plus custom), frame rate (30-120 FPS), bitrate (20-5000 Mbps) and quality presets. Headless use Since version 0.11.0, a Mac without its own display (Mac Studio, Mac mini, or a laptop in clamshell) can run with the tablet as its only screen. Launch at Login and Auto-start streaming let the Mac boot directly into serving the tablet. First-time setup still requires a screen once to grant Screen Recording permission. Requirements - macOS 13 (Ventura) or later on Apple Silicon or Intel. - Android 8.0 (API 26) or later with an H.265 hardware decoder. - USB mode needs a USB-C port, adb installed on the Mac, and USB debugging enabled on the tablet. - Wireless mode needs both devices on the same WiFi network, a camera for QR scanning, and Google Play Services for ML Kit barcode scanning. Installation and build Prebuilt .dmg (macOS) and .apk (Android) releases are provided. Because the macOS app is not notarized, Gatekeeper may report it as damaged; the README suggests running sudo xattr -cr /Applications/SideScreen.app. ADB is required on the Mac and can be installed via Homebrew's android-platform-tools cask. Source builds use swift build -c release for the Mac host and ./gradlew assembleDebug for the Android client. Troubleshooting notes cover connection refused errors, latency and stuttering, wireless pairing failures, token resets, the macOS "Displays have separate Spaces" setting that can blank the virtual display during fullscreen apps, and granting Screen Recording permission. The project is MIT licensed, accepts issues and pull requests, and offers optional donation links.