Here is how to make a QR-Code that points to an app in the Market on an Android device. By scanning the QR-Code with the barcode scanner on your phone you will be sent straight to that app on your phone so it can be installed.
First you need to know the unique name of the app. If you are an Android developer you can easily get this by logging into your Developer Console account at Google. Click on the link for the name of your app and it will send you to ‘Upload an Application’. Your unique name for your app is everything in the address bar past ‘p=’.
For example: …Home#AppEditorPlace:p=com.theblaine.toughguy
com.theblaine.toughguy is the unique name of the application
Put that unique name at the end of the Market search address to make it look similar to below. This is the URL the Android device uses when you search the Market on your phone. Since you are searching for a unique name it will take you directly to your app.
Now take this URL and put it into the QR-Code Generator. The resulting icon, if scanned by your phone barcode scanner, should take you directly to your app.