A modern, local-first desktop viewer for Flexcil backup files.
⚡ Fast • 🔎 Full-Text Search • 📂 Folder Structure • 🔐 100% Local
A modern, local-first desktop viewer for Flexcil backup files.
The application allows you to open official Flexcil backup archives on your computer, browse documents, search their contents and display handwritten annotations directly inside the viewer.
⚠️ This project is not affiliated with, endorsed by, or connected to Flexcil in any way.
ToDo-List
- Image Support ✔️
- Folder Structure ✔️
- Launcher with Updater ✔️
- MacOS Build (Have someone a mac? I can build a MacOS dmg (also have Apple Developer Account), but have no mac yet to test.)
- Shape recognition -- 70%
- better ink rendering -- 50%
- 📂 Rebuilds folder structure from
documents.list - 📄 Extracts PDFs from Flexcil backup ZIP /
.flxfiles - ✍️ Displays Flexcil ink annotations (handwritten notes)
- 🔎 Real-time full-text search across documents
- 📑 Jump-to-page navigation
- 🪓 Splitscreen in Viewer
- 🖼 Thumbnail preview grid
- 📊 Import progress indicator
- 💾 IndexedDB local storage
- 🌙 Modern dark UI
- 🔐 100% local – no uploads, no cloud interaction
- 🤌 Download all you PDFs in one ZIP (You can´t use this file as backup to import in the viewer.)
The viewer is capable of displaying Flexcil handwritten annotations directly on top of the original PDF pages. It is in Beta.
This includes:
- pen strokes
- handwriting
- pressure-based ink rendering
Modern folder sidebar with thumbnail grid and metadata overview.
Built-in PDF.js viewer with navigation, zoom, and jump-to-page support.
Instant search across all indexed documents with live updates.
Splitscreenview and TopBar with more than one document.
Can inprint the shape from Flexcil, but still in beta.
If you don’t want to run the development version, you can download the standalone Windows executable from the Releases section.
- Go to the GitHub Releases page.
- Download the latest
.exefile. - Double-click to start the small installer.
- A Launcher Appear with Update function etc.
- Your browser will open automatically.
When a update is availabel, the Launcher can download and Update automatically.
git clone https://github.com/janptn/flexcil-backup-viewer.git
cd flexcil-backup-viewernpm installnpm run devOpen the shown local URL in your browser.
- Download your Flexcil backup ZIP from Google Drive or a manual backup (Both are working since the new Update).
- Drag & drop the ZIP file into the app.
- The app automatically:
- Extracts PDFs
- Rebuilds folder structure
- Indexes document text
- Stores everything locally in IndexedDB
Whenever you create new documents on your tablet:
- Download the latest Flexcil backup ZIP from Google Drive or a manual backup from the App.
- Drag & drop it into the app again.
- The viewer automatically:
- Detects new documents
- Skips already imported ones
- Updates the library instantly
You can repeat this process anytime.
No manual cleanup required.
- No telemetry
- No tracking
- No cloud sync
- No external uploads
- All data stored locally in your browser
You can clear stored data anytime via browser storage settings.
Flexcil is tablet-first.
This tool provides a fast and clean desktop viewing experience without requiring official desktop support.
Built for productivity and open-source collaboration.
Flexcil is a trademark of its respective owners.
This project is an independent viewer for user-generated backup files and does not interact with official Flexcil services.
MIT License © 2026 Jan Pultin