Any Mac on macOS 13 Ventura or later, with either Apple Silicon or an Intel processor. There’s a separate download for each. To check yours, open the Apple menu and choose About This Mac.
Windows 10 and 11 (64-bit) are supported by the app, but the Windows build isn’t published yet. The same account will work on it when it is — nothing to sign up for twice.
Windows 10 or 11, 64-bit. Download Iris-Setup.exe and run it. Windows may show a “Windows protected your PC” screen — choose More info → Run anyway; it appears because the installer is new, not because anything is wrong. Iris asks for the microphone on first launch and needs nothing else: the Screen Recording and Accessibility permissions a Mac requires have no equivalent on Windows.
A few things are Mac-only for now and Iris will say so rather than pretend: switching or closing browser tabs, driving an already-open terminal, Reminders, and WhatsApp. Everything else — voice, her character, screen awareness, apps, volume, clipboard, music, timers — works on both.