Mos is a lightweight macOS utility that smooths mouse scrolling and allows independent control of scroll direction per application and axis.
The tool addresses the problem that standard mouse wheels feel jerky on macOS due to insufficient precision. Mos intercepts mouse scroll events and interpolates them into smoother scrolling behavior while preserving per-application, per-axis, and per-button control. It also enables remapping and rewriting of arbitrary mouse buttons to adapt to individual workflows. The application runs as a menu bar tool and supports macOS 10.13 and later.
Mos suits users who want to make third-party mice feel as responsive as trackpads without sacrificing precision. It is particularly valuable for those who switch between multiple applications with different scrolling needs or who use mice with programmable buttons. The tool offers axis-independent configuration, allowing vertical and horizontal scrolling to be smoothed and reversed separately. Per-application settings let each app inherit global rules or override them entirely. Button binding extends beyond scrolling to system actions, keyboard shortcuts, launching applications, running scripts, and opening files. Support for Logitech devices via HID++ protocol adds compatibility for wireless receivers and Bluetooth connections.
The project maintains a substantial base of adopters who report real-world issues, as evidenced by the fact that almost all open issues originate from outside users rather than the core team. Responses to issues and pull requests typically arrive within one to two weeks. Development activity centers on bug fixes, feature requests, and enhancements as tracked in the issue labels.
