Kaywa QR Code - Kaywa QR Code is a QR-Code Generator.
ZXing - Barcode Scanner for Android
Zint Barcode Generator - A barcode encoding library supporting over 50 symbologies.
QuickMark - QuickMark makes everything possible.
qurify - Online QR Code generator with some advanced settings and print queue.
QR Droid - QR Droid Zapper