gLabels - gLabels is a program for creating labels and business cards for the GNOME desktop environment.
Manatee Works - Manatee Works offers barcode decoding solutions.
QZ Tray - Print raw (ZPL, ESC/P, FGL), HTML, PDF as well as communicate with USB, HID, and serial devices...
BarCodeWiz OnLabel - Barcode and QR Code and Barcode
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.
CodeREADr - A smart barcode scanner app for fast barcode scanning with the device camera or accessory. Create barcode scanning workflows and sync data in the cloud.