QuickMark - QuickMark makes everything possible.
ZXing - Barcode Scanner for Android
QR Code Reader “Q” - Formerly QR Code Reader “Q,” now QRQR, is a smart code reader application.
Barcode to PC: Wi-Fi scanner - Turn your smartphone into a real barcode scanner
Lynkee Reader - Lynkee Reader is the best QR & Barcode Reader application on the market.
bcWebCam - Scan barcodes and QR Codes with your computer web cam