Now that we're closing in on the holiday season, you absolutely must have a bar code scanner. These apps are tremendously popular, and for good reason. You're in a store, you find something you like, you scan the bar code with your iPhone's camera, and then you find out where you can buy it for the lowest price. Typically these apps are location aware, in case you want to buy it at a nearby store. And typically, they also have maps and directions that show you how to get to the store with the lowest price. And — they're free! Why would anyone go without one of these? Shop Savvy Barcode Scanner just came out with a completely revamped 4.0 version. It looks to be one of the most popular. Also available is Red Laser, the venerable app that introduced this genre on the iPhone. And Bakodo is another good option.