Sticky Notes HD is a great iPad note taking app to try out. The app is free right now and only for a limited period of time. It allows you to create memorable sticky notes using a wide variety of features that include 20 beautiful colors, stunning graphics and visuals, customizable notes size, text and color. You can organize your notes using color-codes and be able to sort them by priority, alphabetically or inverse. You also have the option to password protect your notes.