> 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/uwp/get-started/customize.md).

# Customizing your UWP Viewer

Learn how to customize Apryse for your app with PDFViewCtrl. Create custom tools easily with the PDFViewCtrlTools project. Check out the Custom Tool guide for more details. The Apryse uwp SDK streamli

After you have added Apryse to your project and added [`PDFViewCtrl`](/uwp/get-started/viewdoc.md), learn how to customize it for your app.

## Creating a custom Tool

Creating a custom tool to use with the PDFViewCtrl is fairly straight forward. There are several tools implemented in the PDFViewCtrlTools project already. These tools can be used as a base for many other tools or as a reference for a new tool.

For more details please see the [**Custom Tool guide**](/uwp/ui-customization/custom-tool.md).

## Next step

<a href="/uwp/guides.md" class="button primary">Guides</a><a href="/uwp/guides/api.md" class="button primary">API docs</a><a href="/uwp/get-started/samples.md" class="button primary">Samples</a>


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