GitHub’s Loupe lets iPhone users peek inside their devices. The app pulls raw data from public iOS APIs that any third‑party app can access, then displays it without hashing or aggregation. Users see exactly what a tracker can read—locale, time zone, battery level, and more—highlighting the silent fingerprints built into the system in today's environment.

Loupe classifies readings into three tiers based on permission cost. Passive data, such as locale and battery, requires no prompt. Needs Permission includes contacts and location, triggering iOS dialogs. Advanced taps side‑channel tricks like URL‑scheme probing and Keychain persistence, exposing hidden vectors that can survive app reinstalls for privacy research and testing today's security landscape.

Developed almost entirely with AI coding tools, Loupe requires Xcode 26+. The source is MIT‑licensed, but logos and design files belong to Mysk. The project ships a macOS build too, though some polish remains. Users can run it locally, copy the signing file, and explore their device without data leaving the machine for privacy insights today.

Free and open source, Loupe invites developers to audit its code and extend its tiers. The author promotes Psylo, a privacy‑first browser that blocks fingerprinting, as complementary work. By exposing the data surface, Loupe supplies a practical tool for engineers to assess how easily apps can re‑identify users across services for modern apps today.