PDFCrowd - Pdfcrowd is a Web/HTML to PDF online service. Convert HTML to PDF online in the browser or in your PHP, Python, Ruby, .NET, Java apps via the REST API.
iSpring Convert - Convert PowerPoint to HTML5 and MP4 video
DocRaptor - As the only API powered by the Prince HTML-to-PDF engine, DocRaptor provides the best support for complex PDFs with powerful support for headers, page breaks, page numbers, flexbox, watermarks, accessible PDFs, and much more
PPTX to Video - PPTX to Video is a simple but powerful mobile application that lets you convert a PowerPoint file to MP4 and play it on any video player.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Converter365 Convert PPT to MP4 - Converter365 is an online freeware converter tool that enables you to convert PPT to MP4 with great ease.