You paid a lot for your iPhone, so why not use it to earn back some of that dough?
Here are seven apps -- all free -- that can save you hundreds of dollars a year. We took them for a test drive and slashed our shopping tab by nearly $70.
Price Check: Ever wonder if you're getting the best deal? There are quite a few apps that promise to scan barcodes and compare prices, but this one is by far the easiest I've used. You can scan a barcode, take a photo, or even just say a product's name, and Price Check will find matches at Amazon.com and any of its hundreds of partners. If the app turns up a better price, just click to buy and save.
Sample savings: A hardcover book selling for $25.99 at Target was just $14.75 at Amazon.
Key Ring: Store loyalty cards often mean serious savings, especially at grocers and drugstores. But the resulting bulge in my wallet from all that plastic means I increasingly turn down offers for new ones, leaving money on the table. Enter Key Ring. It scans and stores all your loyalty cards so they're always just a tap away.
Sample savings: $3 off my cats' favorite brand of food at Petco.
Amazon Deals: For the uninitiated, Amazon (AMZN) offers up one huge "Deal of the Day" and a half-dozen or so "Lightning Deals" every day, good for just a few hours each. These deals often mean massive savings on items like printers, HDTVs, cameras, video games, and more. The problem? The discounts are so good that the deals often sell out. Amazon Deals comes to the rescue with a simple app that alerts you to current and upcoming offers, and lets you buy current deals instantly or get a text reminder for future ones.
Sample savings: $12.55 (33%) off a surge protector, $30 (41% off) a pair of high-tech ear buds.
Gas Buddy: This ingenious app uses your location to display the prices at every nearby gas station, thanks to fellow users who update prices regularly. (In my area, they're usually current within an hour or two.) The first time I used it, I saved $3.60 simply by skipping the station across from my house and stopping at one a little further along my regular route.
Sample savings: $3 less per tank.
Grocery iQ: Every once in a while, I try to clip coupons to save a little cash, but inevitably, I never have them with me when I need them. Grocery iQ has the solution: Add coupons directly to your grocery store savings card! That way, they're applied instantly at checkout. The app does some other cool things, too: You can scan items as you run out of them to add them to a shopping list; organize your list by store and aisle; and print additional coupons directly from your phone. The selection of stores participating in the savings card portion is somewhat limited (developers promise they're adding more all the time), but if yours is included, this app is a must.
Sample savings: $0.75 off ice cream, $2 off multivitamins.
Groupon: Until recently, I didn't quite get the immense popularity of Groupon. You had to keep track of which deals you'd bought and remember to use them before they expired. That's easier said than done for this busy mom of two. But thanks to the genius combination of Groupon's instant deals with its mobile app, I'm now a Groupon groupie. Using your location, Groupon will point you to deals close by. A recent search turned up three restaurant offers within walking distance of our offices, plus a handful of salon and shopping choices.
Sample savings: $5 for $10 worth of food at a favorite lunch spot.
Yard Sale Mapper: If you're a fan of garage and yard sales, this is the app for you. Pulling from Craigslist and newspaper listings, Yard Sale Mapper displays all the sales in your area by day. Simple yet indispensible for the true bargain hunter.
Sample savings: Unlimited!
Got a favorite money-saving app not mentioned here? Comment and let us know!
Motley Fool writer Robyn Gearey owns an iPhone, but does not own shares of any company mentioned here. Motley Fool newsletter services have recommended buying shares of Amazon.com.