01
Lock macOS apps
Protect Messages, Mail, notes, finance tools, work apps, or any selected app with an overlay that appears during launch and app switching.
Local-first privacy for macOS
MacShield
One security system for macOS apps and Chrome.
MacShield protects the desktop and the browser together: native app locks for macOS, Website Lock for Chrome, and privacy blur for sensitive conversations.
No account
No analytics
Open source
Local storage
macOS app lock
Messages
Mail
Notes
App protected
Touch ID, Watch, or password
Local auth
Chrome extension
Website locked
Passkey or password before content renders
Product pillars
One privacy layer for apps, chats, and websites.
MacShield is structured around three clear jobs: cover private app content, blur sensitive conversations, and block chosen websites until the right person authenticates.
02
Blur private content
Reduce shoulder-surfing risk by blurring sensitive chat content and revealing only the parts you actively choose to read.
03
Lock browser sites
Add custom domains to Website Lock, then require authentication before pages such as dashboards, mail, or social tools render.
Protection map
Choose the layer that matches the risk.
Situation
Protection
Unlock
Where data stays
Someone opens a private app
Full-screen app overlay
Touch ID, Apple Watch, or password
On your Mac
A chat is visible during work
Blur or hide mode
Hover, select, or toggle
Local UI only
A protected website loads
Browser lock screen
Password or platform biometric
Chrome local/session storage
Setup flow
From install to protected in four steps.
1
Install
Download the latest release, move MacShield to Applications, and launch it from the menu bar.
2
Grant access
Enable the macOS permissions needed for app detection, overlays, blur, and optional watch proximity.
3
Add targets
Select protected apps, configure blur behavior, and optionally add browser domains to Website Lock.
4
Authenticate
Unlock with Touch ID, Apple Watch proximity, or password fallback when protected content is accessed.
Native macOS app
Built for the moments when private app content flashes on screen.
MacShield lives quietly in the menu bar and watches protected app launches and activations. When a protected app opens or returns to focus, MacShield covers the screen until the user authenticates.
- Touch ID through Apple's LocalAuthentication framework.
- Password fallback stored through the macOS Keychain.
- Apple Watch proximity unlock and relock where configured.
- Idle, sleep, and optional auto-close protections.
Passkey
Authorize with Touch ID or device biometric
Place your finger to begin
Scanning fingerprint…
✓ Authenticated
Browser extension
Blur supported platforms. Lock any domain you choose.
The extension is structured around local Chrome storage, Web Crypto password hashing, WebAuthn where available, and CSS-based blur rules that do not read message content.
- WhatsApp, Gmail, Slack, Discord, Teams, Telegram, Messenger, LinkedIn, X, Outlook, Facebook, Signal, and Element support.
- Custom Website Lock for work tools, social sites, mail, finance, and admin dashboards.
- Session unlocks clear when Chrome closes.
WhatsAppGmailSlackDiscordTeamsTelegramOutlookLinkedInElement
Use cases
Designed around real privacy pressure.
Open offices
Keep messages and mail readable only when you intentionally reveal them.
Shared Macs
Lock apps and browser sites without relying on cloud accounts or subscriptions.
Client work
Protect confidential chats, roadmaps, contracts, and internal dashboards during context switches.
Walk-away moments
Auto-lock or auto-close sensitive apps when you sleep, idle, or leave watch range.
Trust and ownership
Clear permissions, proper credits, and no hidden backend.
Local by default
No analytics, advertising SDKs, hosted accounts, or product telemetry pipeline. Protected app settings and extension preferences stay local.
Documented permissions
Accessibility, Bluetooth, Screen Recording, Chrome storage, tabs, and all URLs are explained in plain language in the docs.
Proper attribution
Credits are documented for MakLock, Sparkle, HotKey, Apple frameworks, Chrome APIs, Web Crypto, WebAuthn, and contributors.
Resource hub
Everything important has a proper page.
Documentation
Install, setup, browser extension, permissions, examples, architecture, troubleshooting, FAQ, contributing, and changelog.
Help and support
Support categories, bug report guidance, troubleshooting flow, and response expectations for the open-source project.
Legal and credits
Copyright, terms, privacy, ownership, dependency attribution, third-party rights, roadmap, and system health.
FAQ
Common questions
Does MacShield collect personal data?
No. MacShield has no analytics, advertising SDKs, or hosted account service. See the privacy policy for exact local storage and permission details.
Why does the macOS app need Accessibility permission?
It needs app activation visibility to detect when protected apps launch or return to focus, so private content can be covered immediately.
Why does the extension need all URLs?
Website Lock supports user-selected domains. To lock arbitrary domains before content renders, the lock guard must be allowed to run on all URLs.
What happens if I forget my extension password?
The extension stores only a salted one-way hash, so there is no recovery backdoor. Remove and reinstall the extension to reset local extension state.
Start with the docs
Install MacShield only after you understand the permissions.
Security tools should be reviewed before use. Read setup, verify the source, enable only the features you need, then protect your first app.