LOWEST PRICE: $135.85 ($124.36, plus $11.49 shipping)
This app found the same price from Amazon and linked to the Amazon website. The app does search for nearby store prices, but it wasn't as extensive as the Google app. It only found one physical store price, but it wasn't cheaper than the price available on Amazon.
LOWEST PRICE: $148.95
This app is owned by eBay Inc., the online marketplace. The lowest price was from an online retailer. Even though this app didn't find the best price for the juice machine, it's worth downloading. You can scan in loyalty cards for certain supermarket and drugstore chains, so you hand over your phone to the cashier instead of carrying a bunch of cards. It lets you buy items within the app from retailers such as Toys R Us and Best Buy and also posts coupons.
LOWEST PRICE: $149.99
This app is also owned by eBay. This app shows prices for brick-and-mortar stores, not online retailers. The lowest price it found for the juice machine was at a Macy's store, but it didn't pick up the sale price of $131.99 like the Google app did. This app matched the price of the item at the Bed Bath & Beyond store, but it's still worth downloading if you are looking to buy something right away and can't wait for it to be shipped.
Hardcore deal seekers will want to download all five apps. But if you don't want to spend the time scanning barcodes five times, at least download these three: Google Shopper, Amazon Mobile and RedLaser. Google Shopper saved me $18, the most of the bunch. Amazon's came in a close second. I'm going to continue to use it, because it's convenient to buy from the app. RedLaser's price was just a dollar less than Bed, Bath and Beyond's, but the app has more features than others. I'll use the loyalty card scanner and check for any coupons.
Joseph Pisani can be reached at http://twitter.com/josephpisani