Tiffany & Co Engagement Ring Finder Cost: Free Tiffany's ( TIF) Engagement Ring Finder is designed for brides-to-be dreaming of receiving one of the famous jeweler's diamond rings. The app lets users view diamonds by shapes, settings, metals and designs, and users can browse stones of up to six different carat sizes. While all of the rings are shown true-to-size, users can also zoom in to view the ring's details and pair it with a wedding band. The rings can be saved within the app to be viewed later and shared via e-mail, Facebook and Twitter, though they can't be purchased through the app. For that, customers need to make an appointment for a diamond consultation, which they can do by sending a note to Tiffany's via the app. The app's best feature: a ring sizer that allows users to place a ring they already own on the screen of their iPhone and align it with the circle guide to determine their ring size. Tiffany's is also planning a new update for the app sometime this summer. Though the company wouldn't comment on specifics, reports have said the app will let users create a private Facebook page to share saved rings and see comments from friends. You'll also be able to view rings on different hand models.