GroupDocs
GroupDocs creates easy to use, comprehensive online document management APIs for .NET, Java and Cloud, as well as a range of Cloud apps that improve document collaboration for organizations of any size. GroupDocs saves developers and end users time and money by offering a complete and powerful set of document management APIs allowing users to view, sign, annotate, compare, convert and assemble documents in a wide variety of formats, including Microsoft Word, Excel, PowerPoint and Visio, as well as Adobe Acrobat PDF and many image formats. Flexible workflows and easy-to-use, customizable user interfaces are part of the package.
Telerik
Progress Telerik offers a leading platform for developing and deploying mission-critical business applications. The creator of the award-winning .NET and Kendo UI JavaScript user interface components/controls, reporting solutions and productivity tools, Progress Telerik has been providing the tools developers need to easily and efficiently build high-performant modern apps with outstanding UI for more than 20 years.
With free on-demand product training (refreshed with every major release) and unparalleled support provided by the same engineers who built the products, they ensure you are successful with their tools from the initial evaluation to release of your application.
Building a modern UI for web, desktop and mobile apps has never been easier.