What is glance?

Glance is a PDF viewer built specifically for Windows 11. It aims to be fast and lightweight while looking like a native part of the operating system, using the translucent Mica background effect and matching whatever light or dark theme the system uses. The interface takes inspiration from simple document viewers like GNOME Evince for browsing, combined with annotation tools closer to what Adobe Acrobat offers. When you open the app you land on a welcome screen showing a grid of recently opened documents with thumbnail previews of each file's first page. From there you can open a PDF and use several editing tools: freehand drawing with a pen for sketches, signatures, or handwritten notes, a highlighter with seven color choices that only shows up while you are actively editing, and sticky notes you can drop anywhere on a page to leave written comments. You can also rotate pages in 90 degree steps, undo any annotation with Ctrl+Z, and compare two PDFs side by side in a split view. Any notes, highlights, or drawings are saved automatically to a local file the moment you lift your pen or mouse, so nothing is lost. If you try to close a document with unsaved changes and autosave is off, it asks whether to save, discard, or cancel. The interface is available in Spanish and English, matching your system language automatically. Under the hood, Glance combines two languages: the visible app is written in C# using WinUI 3, Microsoft's framework for modern Windows desktop interfaces, while the actual PDF rendering and file storage work happens in a separate Rust backend for speed. The two sides talk to each other through a bridge that lets C# call Rust code directly. Rendering itself relies on Google's PDFium library, and edits get written back into the PDF file using an open source library called PDFsharp. To build it yourself you need the .NET 10.0 SDK and Rust 1.70 or newer, plus optionally Visual Studio 2022. It runs on Windows 10 or later, requires version 1.5 or higher of the Windows App SDK, and is released under the MIT license.