It's funny. As the cameras in our iPhones get more spectacular capabilities, more apps are appearing every day to give those beautiful high-resolution photos scratches, tints, and frames that make them look well, not so nice.
Analog (RealMac Software, US$7.99 introductory price) is another Mac app that lets you change the look of your photos with an assortment of filters and borders. Others that you might want to check out before you make your choice are Flare ($9.99 through the Mac App Store right now or $19.95 on the Iconfactory website) and FX Photo Studi