PDFium - The C# PDF Library to Create and Edit PDF documents in .
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
PDF Shaper - a collection of PDF tools and utilities to modify and optimize your PDF documents and its content
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.
PDF Bob - PDF Bob is a free online PDF editor that can both edit PDF and annotate PDF. One can edit text, add text, highlight, strikeout and underline text in PDF, add comments and pictures, add lines, arrows, rectangles, circles... read more.
PDFSwitch - Convert any HTML document or URL to PDF with a single API request.