iOS is a highly modal operating system, forcing one application at a time upon the user. Not only are we limited to one application, but we're also limited in space and possible views at any given time when inside our application.
In this recipe, we'll define modal views and the role they play in our application.
Modal views are more prevalent and easy to distinguish on the iPhone and iPod touch, so we should look to have one of these two devices on hand. Modal views do occur on the iPad as well, so it would be helpful to also have this device if possible.
Apple has devised several different modal views for our disposal. One modal view only works on the iPhone, only three work on the iPad, ...