OwlOCR - OwlOCR offers simple optical character recognition of text in PDF files, images or on-screen and converts that to plain text.
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
CONV. - Convert YouTube video to MP3, GIF or MP4
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.
FFmpeg - Open source multimedia suite for conversion, playback, profiling, and streaming.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request