QZ Tray - Print raw (ZPL, ESC/P, FGL), HTML, PDF as well as communicate with USB, HID, and serial devices...
ezeep - ezeep provides managed cloud printing solutions for educational institutes and SMB's.
Printer Pro - Print attachments, receipts, documents, web pages from your iPad and iPhone.
PrintNode - PrintNode offers cloud printing solutions for web applications.
Breezy - Breezy is a secure cloud printing solution that makes it easy to print from any device to any printer on any network.
Printix - Printix is a cloud-based print management platform.