Apps. are great, but who has time to search for them? Here is my favorite handy design app.: iHandy Carpenter, a handy tool app for your smart phone has five different tools. My favorite is the bubble level, great for hanging small pictures in a pinch. You can also just get the level app. which is a free download. Other tools include a plumb, protractor, ruler, and a surface level (you know for checking up on the tile guy). What is your favorite phone app.?