After playing with this app for the last week or two, I like it. I don't' see why I would need to purchase the full version but I do like this. I know between me and my wife we said that the only thing that this is missing is the ability to sync lists together. We make grocery lists throughout the week and we keep them synced on our phones and they mimic each other just in case somebody is out and buys milk, the other won't buy milk as well. I would recommend some sort of sync feature if it's possible.
Other than that, great job.