PdfViewer is a simple Android app for opening and reading PDF files, built by GrapheneOS using pdf.js. It is designed around security: the app requests no permissions and isolates the PDF content from the rest of your device while rendering it.
Developer: GrapheneOS · License: MIT (open source) · Price: Free
Official file from the developer's release · Jul 30, 2026 · SHA-256 8baf331478b72e5f…
Key features
- Opens PDF files via content providers, no permissions required
- Uses pdf.js inside a sandboxed WebView to render documents
- The WebView has no access to the network, files, content providers or other app data
- Content-Security-Policy locks JavaScript and styling to static content from the APK assets, and blocks custom fonts
- Reuses the hardened Chromium rendering stack while exposing only a small subset of its attack surface
Why isn’t GrapheneOS PDF Viewer on Google Play?
PdfViewer is published by GrapheneOS on GitHub rather than distributed through Google Play, and it is not listed on F-Droid either.
Is GrapheneOS PDF Viewer safe?
This is an open-source project (MIT license) from the GrapheneOS team, and the APK comes from their official GitHub releases. The app requests no Android permissions, and the README describes the PDF rendering sandbox in detail, though as with any APK installed outside an app store you should download it only from the official GitHub repo. GrapheneOS PDF Viewer comes straight from its developer rather than through Google Play, so it hasn’t gone through Google’s app review. As with any app, check the permissions it asks for and install it if you’re comfortable with them.
How to install
- Tap the download button above: the APK file downloads straight to your phone.
- When Android asks, allow your browser to install unknown apps.
- Open the file and tap Install.
FAQ
Is PdfViewer free?
Yes. It is open source under the MIT license, and you can download the APK from its GitHub releases page.
Does PdfViewer need any permissions to work?
No. According to the README, the app doesn't require any permissions. It receives the PDF stream through a content provider and feeds it into an isolated WebView.
How is this different from a regular PDF viewer or browser-based PDF rendering?
The PDF content is rendered using pdf.js inside a sandboxed WebView that has no access to the network, files, content providers or other data, and a Content-Security-Policy restricts scripts and styles to static APK assets. This limits what an attacker could do even if they exploited the rendering engine.
More free apps you won’t find on Google Play: Open Source Apps · Best Android apps not on the Google Play Store.
Frequently Asked Questions
Is PdfViewer free?
Yes. It is open source under the MIT license, and you can download the APK from its GitHub releases page.
Does PdfViewer need any permissions to work?
No. According to the README, the app doesn't require any permissions. It receives the PDF stream through a content provider and feeds it into an isolated WebView.
How is this different from a regular PDF viewer or browser-based PDF rendering?
The PDF content is rendered using pdf.js inside a sandboxed WebView that has no access to the network, files, content providers or other data, and a Content-Security-Policy restricts scripts and styles to static APK assets. This limits what an attacker could do even if they exploited the rendering engine.
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