Engineered for creators.
Comprehensive guides for driverless iPhone USB capture, Android ADB reverse streaming, OBS Studio broadcast setup, and troubleshooting.
Choose your primary workflow
iPhone to Mac (USB)
Driverless CoreMediaIO pipeline with zero-copy Metal texture rendering and raw 48kHz IDAM audio.
Android USB Gaming
Mapped local reverse TCP tunneling with 48kHz internal game sound via AudioPlaybackCapture.
OBS Studio Setup
Direct GPU memory sharing via Windows Graphics Capture and macOS ScreenCaptureKit with isolated audio.
Verified Routes & Hardware Targets
| Device | Host Receiver | Connection | Mobile App? | Audio Pipeline | Latency | Status |
|---|---|---|---|---|---|---|
| iPhone / iPad | Apple Mac (macOS 14+) | USB Cable | NO (Zero-App) | Uncompressed IDAM 48kHz | 12 – 18 ms | Supported |
| Android | Mac / Windows / Linux | USB (ADB) | Yes (Companion APK) | AudioPlaybackCapture 48kHz | 25 – 35 ms | Supported |
| iPhone / iPad | Windows 10/11 | USB Hotspot | Optional (AirPlay Mode) | WASAPI 48kHz Shared | ~24 ms | Supported |
| iPhone / iPad | Mac / Windows / Linux | Wi-Fi (5 GHz) | Yes (CastSprint iOS) | ReplayKit PCM / AAC | 20 – 35 ms | Supported |
| Android | Windows / Mac / Linux | Wi-Fi (5 GHz) | Yes (Companion APK) | AudioPlaybackCapture 48kHz | 45 – 65 ms | Supported |
| iPhone / iPad | Apple Mac / Windows | AirPlay (LAN) | NO (Zero-App) | AirPlay 2 Audio Stream | 80 – 150 ms | Demo / Presentation |
All Guides & Specifications
iPhone USB Screen Mirroring
Zero-app wired capture on macOS with sub-15ms Metal rendering, and USB Hotspot mode on Windows with WASAPI audio.
Android USB Gaming & ADB
High-speed USB streaming with reverse port tunneling, 48kHz internal game audio via AudioPlaybackCapture, and locked 60 FPS.
Local Wi-Fi & AirPlay Mirroring
Cable-free streaming over 5GHz Wi-Fi with mDNS discovery, SHA-256 certificate pinning, 6-digit session PINs, and native AirPlay.
OBS Studio Livestreaming Setup
Complete guide to zero-copy Window Capture (WGC / ScreenCaptureKit), isolated Application Audio Capture, and aspect ratio framing.
Installation & Platform Setup
Installation guide and security verification for macOS DMG, Windows portable x64, Linux PipeWire receiver, and Android companion APK.
Troubleshooting & Diagnostics
Step-by-step diagnostic checklist for black screen DRM, ADB authorization, Wi-Fi discovery, audio desync, and firewall issues.
Architecture & Latency Benchmarks
Deep-dive into Protocol V1 framing, hardware AV synchronization, zero-copy Metal/D3D11 rendering, and verified latency benchmarks.
Why streamers rely on CastSprint
Commercial screen mirroring software locks high frame rates behind paywalls, plasters intrusive watermarks across mobile tournament gameplay, or pipes video through remote cloud servers. CastSprint does none of that.
100% Free & Private
Zero paywalls, zero watermarks, zero accounts, and zero telemetry. Video stays strictly on your physical USB wire or private home subnet.
Hardware AV Synchronization
Proprietary monotonic clock regression alignment (AvSynchronizer) guarantees game sound and action stay locked in sync during multi-hour livestreams.
Zero-Copy GPU Presentation
Decoded frames stay entirely in VRAM via Metal CVMetalTextureCache and Direct3D 11 flip-discard swapchains for sub-frame presentation.