MirrorMask

MirrorMask is a native macOS utility that accesses a user’s Google ad profile, then modifies the profile by automatically browsing the web under a selected alternate persona. Each night the app opens the existing Chrome session and performs searches, watches YouTube videos, and visits social‑media and forum pages as the chosen identity, without requiring passwords or altering any accounts. All activity is performed locally on the Mac, and no personal data leaves the device.

The tool targets users who want to influence how advertising and recommendation algorithms perceive them, either to reduce tracking effectiveness or to diversify the content they receive. It offers a set of ten pre‑defined personas—such as Fisherman, Home Chef, or Tech Enthusiast—and allows creation of custom identities. By injecting noise into the algorithm’s view of the user, MirrorMask aims to make the real interests statistically invisible while preserving privacy.

MirrorMask runs on macOS 14 or later, is built with Swift, and operates without subscriptions or external services. It emphasizes local processing, avoids credential prompts, and reports only anonymous telemetry, positioning itself as an experimental solution for algorithmic self‑determination.