Color Splash: (99 cents, Pocket Pixels): A friend has posted neat photos using this program. It turns your photo into black and white, and then you can choose to add splashes of color back to it. I think I might need the tutorials to figure it out, but they are available, and the effects that I have seen are worth the time.
And when you're through editing your photos, try uploading them via apps such as Flickr (free, Yahoo), DailyBoothApp (free, DailyBooth) or Instagram (free, Burbn) and sharing them with friends or strangers.
Stay tuned for more to come in this column. While you're waiting, check out Hipstamatic for taking pictures and SwankoLab for editing them (both $1.99 from Synthetic Infatuation) on your own. These popular apps are among those that let you create some unusual effects.