QuietGlass

Product Introduction

1. Definition: QuietGlass is a native macOS menu bar application (built with SwiftUI and AppKit) designed for on-device screen privacy. It is an open-source utility that leverages system frameworks like ScreenCaptureKit, Core Motion, AVFoundation, and Vision to dynamically control screen visibility.
2. Core Value Proposition: It exists to provide proactive, context-aware screen privacy for Mac users in shared environments. Its primary value is preventing visual hacking (shoulder surfing) by automatically blurring screen content when you look away using AirPods or when the camera detects another person nearby, all while processing data locally on your Mac for maximum security.

Main Features

1. AirPods-Powered Look-Away Protection: This feature uses the motion sensors in compatible AirPods (via Apple's Core Motion framework) to detect changes in head orientation. When you turn your head away from the screen, the app triggers a real-time screen blur using Core Image filters. It requires a one-time calibration to establish a baseline "looking at screen" position. This enables hands-free privacy without manual intervention.
2. Camera-Based Nearby People Detection: Utilizing the Mac's built-in camera and Apple's Vision framework for face detection, this feature monitors the field of view for additional faces. If an unauthorized person is detected within view, it can either provide a discrete on-screen warning or automatically blur the screen—even while you are still looking at it. This addresses the critical privacy gap where someone looks over your shoulder.
3. Optional Biometric Owner Recognition (Recognize Me): This advanced feature adds a layer of authentication to camera protection. It uses Core ML with a bundled SFace model to enroll and recognize the device owner's face. Before clearing a blur triggered by the camera, the user must perform a short, randomized movement sequence (like turning their head) which is matched against a securely stored template in the macOS Keychain, authorized via Touch ID or password.
4. Flexible Manual Protection Modes: Beyond automation, QuietGlass offers granular manual control. Users can instantly blur all screens with a hotkey (⌃⌥⌘P), protect a specific application window, draw a custom area to blur, or use "Focus Mode" which keeps only the active window clear while obscuring all other screen content. These modes work independently of AirPods or camera hardware.
5. Local Sensitive Text Detection: The app uses on-device text recognition (Vision framework) to scan for predefined sensitive content patterns or custom phrases entered by the user. When detected, it can automatically blur the surrounding area, helping to protect information like passwords, API keys, or confidential data visible on screen.

Problems Solved

1. Pain Point – Visual Information Leakage in Public Spaces: The primary problem is shoulder surfing and inadvertent screen exposure in coffee shops, open-plan offices, airplanes, and co-working spaces. Traditional solutions like privacy screens are static and reduce screen quality, while manual locking (⌘Ctrl+Q) is disruptive to workflow.
2. Target Audience: The core user personas include remote workers and digital nomads in public spaces, professionals handling sensitive data (developers, lawyers, financial analysts) in shared offices, students in libraries or labs, and any Mac user concerned about screen privacy in transient environments.
3. Use Cases: Essential scenarios include: working on confidential documents or code on a train; taking a video call in a cafe where sensitive information is on screen; reviewing financial spreadsheets in an airport lounge; or coding in an open office where passersby could see API keys or credentials in a terminal window.

Unique Advantages

1. Differentiation vs. Competitors: Unlike simple screen dimming apps or physical privacy filters, QuietGlass offers dynamic, context-aware protection. It differs from other "look away" apps by deeply integrating multiple macOS-native frameworks (Core Motion, Vision, Core ML) for a seamless experience and adding the innovative "Nearby People" detection that works even while the user is attentive. Its open-source nature also provides transparency that closed-source alternatives lack.
2. Key Innovation – Hybrid Sensor Fusion for Proactive Privacy: The key technological innovation is the combination of wearable motion data (AirPods) and computer vision (built-in camera) to create a multi-layered privacy system. This "sensor fusion" approach allows it to protect against both intentional looking away and threats that occur while the user is engaged, a significant step beyond single-sensor solutions. The local, on-device processing of all camera and screen data is a fundamental privacy-first architectural decision.

Frequently Asked Questions (FAQ)

1. Does QuietGlass work without AirPods? Yes, QuietGlass functions fully without AirPods. All manual protection modes (full screen blur, window/area protection, Focus mode) and the camera-based "Nearby People" detection feature work independently. AirPods are only required for the automatic look-away head tracking feature.
2. Is QuietGlass secure and private? Where is my data processed? QuietGlass is designed with a privacy-first architecture. All processing—including screen capture, text recognition, camera face detection, and owner face matching—occurs locally on your Mac. No screen data, camera frames, or biometric templates are uploaded to the cloud. The optional owner face template is stored encrypted in the macOS Keychain.
3. What macOS permissions does QuietGlass require and why? The app requires Screen Recording permission to capture and blur screen content, Motion & Fitness to read head-tracking data from AirPods, and Camera access for nearby-person detection and owner recognition. These are standard macOS permissions for the stated functionalities.
4. How does the "Recognize Me" owner recognition feature work? This optional feature uses the Mac's camera and a local Core ML model to create a mathematical representation (template) of your face. This template is saved securely. When camera protection is triggered, it prompts you to perform a simple movement; it then verifies both that a face is present and that it matches the enrolled template before clearing the blur, preventing unauthorized clearing by someone else.
5. Can I use QuietGlass on a Mac with a notch? Yes, QuietGlass is fully compatible with MacBook Pro models featuring a notch. The app's control interface is designed to integrate with the macOS menu bar and provides controls that are accessible alongside the notch area.