FLATHUB - Apps for Linux, right here
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.
Snap Store - An in-app shopping experience from Snapchat 🐶🔥
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
AppImageKit - Linux apps that run anywhere
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request