We were recently over at our local grocery store perusing the selection of laundry detergent when we overheard a couple people discussing the merits of certain detergent formulas ("...this one isn't tested on animals and is made with plant oils"). But after they left we noticed some of the info they mentioned wasn't correct after carefully checking the labels. The GoodGuide is an iPhone app that could have come in handy in this sort of situation. With data about over 65,000 products, ranging from toothpaste, shampoo, household cleaners and just about any other home product which you might have concerns about using in and around the home, the GoodGuide is a careful shopper's dream app (and free!)
Searching and navigation is simple, with a search option or a featured products list that might steer you to certain green-friendly products. We also signed up for a free account, which allows us to create custom shopping lists and items you've already deemed "good to use" or "to avoid". You can share this list online at the GoodGuide website with friends and other users. And best yet, the app is free (and can be used on your iPod Touch for iPhone posers such as ourselves) and also available for non-iPhone users (though the iPhone version is much better from a UI standpoint. Download info here.