Henri, if you have an old iPhone, the app might not work properly if you have an older iOS on it. The app requires iOS 4.1 or newer.
I have already added the Tim Holtz special edition ink pad sets (both Fall and Winter) to the product database because I happen to have the barcodes for those two sets.
So you just search for the limited edition distress ink pads and add those to your own stash list. No scanning needed. And since those ink pads come in sets of three, they are not registered as separate but as sets.
Have a nice lunch with your scrap friend!