gLabels - gLabels is a program for creating labels and business cards for the GNOME desktop environment.
Printix - Printix is a cloud-based print management platform.
QZ Tray - Print raw (ZPL, ESC/P, FGL), HTML, PDF as well as communicate with USB, HID, and serial devices...
PrinterLogic - PrinterLogic is an enterprise print management software.
NiceLabel - NiceLabel is a label design and label management systems that help companies of all sizes to enhance the quality, efficiency and speed of their labelling while reducing cost.
directprint.io - Printer management for Chromebooks & Windows.