push4site.com - Push4site.com service instant browser push notifications.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Gotify - a simple self-hosted server for sending and receiving messages
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
Amazon SNS - Fully managed pub/sub messaging for microservices, distributed systems, and serverless applications
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.