The Mail app has cleverly boiled down the most useful features you're likely to use on your device. The act of sending and receiving an e-mail is accomplished in a minimal number of taps, and the interface is smooth and intuitive. In addition, you can customize many features to suit your specific needs. You can change the default signature, the size of text, the way your inbox appears, and more. Here are some ways to get the most out of your Mail app.