Feature Proposal: CrossRun

Hi everyone!

I've considered this — what if Apple added a native system-wide feature in all of iOS, iPadOS, and macOS called “CrossRun” where you can natively execute non-App Store software like Windows or Linux apps natively on your device? But not in a sluggish emulator—this would use intelligent Apple-signed Just-In-Time (JIT) compilation inside the virtual containers, and the experience would actually perform fast and feel natural.

This is my vision for CrossRun:

Every developer, student, creative professional, and enterprise user who relies on specialized software—whether it’s legacy Windows tools, Linux-only applications, or vintage DOS and Classic Mac utilities—feels the pain of platform lock‑in. Artists can’t run niche Linux‑based graphics programs on their iPads. Engineers can’t test x64‑only binaries on Apple Silicon without juggling emulators. Retro‑gaming fans miss their favorite DOS titles. Even enterprises struggle to standardize on Apple hardware because critical Windows‑only applications won’t run seamlessly.

If we don’t push for CrossRun now, the Apple ecosystem remains siloed: iPads and iPhones will continue limited to App Store apps, Macs will still need multiple third‑party VM tools, and countless workflows stay fragmented across devices. That means slower development cycles, extra licensing costs for virtualization software, and lost opportunities for education, creativity, and business efficiency. Without CrossRun’s universal runtime, we’ll still be rebooting into different environments or paying for separate virtualization apps—year after year.

Apple already provides the building blocks: Rosetta 2, Virtualization.framework, Apple Silicon—and QEMU thrives as open‑source, battle‑tested code. With the next wave of Apple Silicon devices on the horizon, demand for cross‑architecture support, legacy‑app compatibility, and enterprise containerization is only growing. Delaying another year will cost developers, businesses, and users real time and money. Let’s show Apple that the community is ready for a truly universal, system‑integrated solution—right now.

Key features we should demand in CrossRun:

• Built‑in Apple‑signed QEMU for all ISAs (x86, ARM, RISC‑V, PowerPC, 68k, MIPS, etc.)
• Rosetta 2 JIT for seamless macOS and Windows x64 support
• Metal‑backed 3D GPU passthrough and Vulkan→Metal / Direct3D→Metal translation
• Downloadable OS and app containers via the App Store or verified repositories (Ubuntu, Windows ARM/x64, Android, Haiku, ReactOS, FreeBSD, retro OSes)
• Predictive ML pre‑warm cache to speed cold starts
• Dynamic resource scaling (CPU, GPU, RAM) per container
• iCloud‑synced snapshots and shareable VM links for cross‑device continuity
• Customizable on‑screen controls (D‑pad, virtual buttons, trackpad, keyboard) on iPhone, iPad, and macOS
• Secure sandboxing via Virtualization.framework with VM disk encryption and MDM policy enforcement
• Virtual LAN and VPN passthrough for container networking
• Developer tooling (crossrunctl CLI, Xcode debugger integration, CI/CD support)
• Plugin ecosystem and container SDK for community‑published templates and translation layers

Let Apple know it’s time to bake CrossRun into the system and unlock a universal runtime for every app, past and future, across iOS, iPadOS, and macOS.