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
Tix - Tix is a state-of-the-art, cloud-based ticketing system that features fully integrated access controls, event management controls, multi-channel distribution capabilities, and a robust reporting suite.
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.
EventTitans - Top rated event management software
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Brushfire - Brushfire offers tools for online registration and event management.