One of the most useful types of apps to come along with the always online smartphone is the price comparison app. I use two different ones, one RedLaser, looks at the UPC and tells me if there is a comparable price. The other is SnapTell for the ISBN and the covers of books, movies, CD, DVDs and other media. With either app, I can be standing in a store looking at a product and wondering if the price is any good. I simply take out my iPhone, open RedLaser or SnapTell, depending on the product and take a picture of the bar code or, in the case of SnapTell, the cover of the book or movie DVD. Within seconds the app will usually tell me whether or not the product is available locally and at what price and the price online. Look for these and similar apps in either the Apple App Store or in the Android Store. Of course, all of this type of app requires a phone with an Internet connection and a camera. It also helps if the camera is a really high quality one. These programs seem to work better as the cameras have improved their resolution.
There are always exceptions. One of the most obvious and common exceptions is special "house brands" at major retailers. You will take a photo of a bar code at Costco or BestBuy and likely the search will come up with something about the manufacturer but nothing about the particular product. The reason is that the major retailers contract for their own unique brands and UPCs and ISBNs. You can get around this sometimes by searching for the manufacturer and trying to find an equivalent more general model of the product.
One thing you find out pretty fast is that most of the items you see marked way down at mass merchandisers (Walmart, Costco etc.) are products that are just being fazed out or have already been dropped by the manufacturers. You are buying last year's TV, camera or whatever. If the item is a current product, you can usually find a slightly better price online. But don't count on it. Some of the BestBuy bundles are less expensive than you can purchase the items for individually. The same thing holds true at the other major stores also. You will soon begin to realize why Walmart and Costco are so popular. They really do have some items at really good prices. But the opposite is also true, some of the things sold by the larger retailers are slightly to greatly overpriced. They have to make money somehow.
OK, so this post doesn't have anything to do with law, genealogy, ancestors or whatever. But, hey, we need to live. Most of the time my wife doesn't need the computer, she already knows the best price for everything out of her head. But not all of us are so talented. I don't compare prices for day to day stuff, it takes too much time and hasn't turned out to be that helpful. But any kind of out of the ordinary purchase, like a movie, a camera, a TV and similar items are certainly worth the effort and the time.