A new open-source utility called Sill lets Mac users display and control an individual application window, or their entire desktop, from an iPhone or iPad. The software streams video directly from the Mac and sends interaction data back from the mobile device, aiming to provide a lightweight second-screen and remote-control option without requiring an account or a vendor-operated relay server.
Sill for Mac captures the selected content and encodes it as HEVC video. Its companion iPhone and iPad app returns taps, clicks, scrolling and keyboard input to the host computer. Apple Pencil and trackpad input are also supported, allowing a tablet to act as more than a passive display.
The devices can connect over the same local network, through a USB cable or by using a direct wireless connection when no shared network is available. Remote access can also run through a user-controlled VPN such as Tailscale. The project says there is no Sill account and no server between the Mac and the receiving device.
The software is free, carries no advertising or subscription, and is published under the Apache License 2.0. A notarized Mac build is available from the project’s website and through its Homebrew tap, while the mobile app is distributed through Apple’s App Store. Developers can also build the applications from the public source repository.
There are practical limits. Sill displays one Mac window or the full desktop at a time, and it does not transmit Mac audio. Clipboard transfers are restricted to text, capped at 256 KB, and work only when both applications provide clipboard access. The Mac must remain awake with Sill running, and after a restart a user must log in before launch-at-login can start the host.
Security depends on using current versions and the intended pairing flow. Recent releases pair authorized iPhones and iPads and encrypt connections. The project warns that Mac version 0.3.1 and earlier did not encrypt local, cable or direct-wireless sessions and allowed connections without pairing, so those builds should be updated. Users can disable required pairing, but doing so permits any device on the local network to attempt a connection, even though traffic remains encrypted.
The repository is built with Swift and Apple frameworks and does not depend on third-party libraries. Its contribution guidance prioritizes latency over picture quality and requires security reports to be made privately. That narrow design—direct connections, native tools and no hosted account system—distinguishes Sill from broader remote-desktop services, while its video, audio and wake limitations keep expectations focused on interactive window access rather than full remote administration.
