What app do you recommend to scan q-codes?
There are a number of apps that work well and are available on multiple platforms for free. Google Goggles is an excellent tool that enables “visual search” including q-codes. ScanLife supports a number of mobile platforms and recognizes multiple types of barcodes. i-nigma and RedLaser are a couple of other popular options. Any app that can scan a QR code will work. The app store for you phone will have a number of options.