> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/core/viewer.md). # Viewer - [Server/Desktop PDF Viewer Library](https://docs.apryse.com/core/viewer/viewer.md): Apryse delivers a robust document viewer that supports text selection, search, and multiple page view modes, making it ideal for dynamic document handling. With features like zoom and fit modes, it en - [View a PDF document on Server/Desktop](https://docs.apryse.com/core/viewer/viewing.md): Discover how to use the PDF Viewer Control in a basic project with full source code. Implement document navigation, text highlighting, markup, and editing effortlessly. The Apryse Server SDK streamli - [Convert between different coordinates on Server/Desktop](https://docs.apryse.com/core/viewer/coordinates.md): Convert PDF coordinates with ease using PDFViewCtrl. Learn how PDF page, screen, and scrolling coordinates work and how to navigate them effectively. Master the art of coordinate systems for precise P - [PDF viewer code samples on Server/Desktop](https://docs.apryse.com/core/viewer/samples.md): Discover how to customize the PDF Viewer Control with advanced tools and GUI elements in this sample. Learn about the Simple version for basic projects. The Apryse Server SDK streamlines secure docume - [APIs for PDF Viewer on Server/Desktop](https://docs.apryse.com/core/viewer/apis.md): Discover utility classes for viewing PDF documents in C++, Java, Android, .NET, and iOS with PDFTron SDK. Enhance your PDF viewing experience with PDFViewCtrl and OpenURLAsync functionalities. The Apr --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.apryse.com/core/viewer.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.