Datasheet

Chapter 1: The iPhone and iPod touch Development Platform
8
The Finger Is Not a Mouse
As you develop applications for iPhone and iPod touch, one key design consideration that you need to
drill into your consciousness is that the finger is not a mouse . On the desktop, a user can use a variety of
input devices — such as an Apple Mighty Mouse, a Logitech trackball, or a laptop touchpad. But, on
screen, the mouse pointer for each of these pieces of hardware is always identical in shape, size, and
behavior. However, on iPhone and iPod touch, the pointing device is always going to be unique.
Ballerinas, for example, will probably input with tiny, thin fingers, while NFL players will use big, fat
input devices. Most of the rest of us will fall somewhere in between. Additionally, fingers are also not
nearly as precise as mouse pointers are, making interface sizing and positioning issues very important,
whether you are creating an iPhone/iPod touch – friendly Web site or a full - fledged iPhone/iPod touch
application.
Additionally, finger input does not always correspond to a mouse input. A mouse has a left click, right
click, scroll, and mouse move. In contrast, a finger has a tap, flick, drag, and pinch. However, as an
application developer, you will want to manage what types of gestures your application supports. Some
Figure 1-10: Application emulating Apple UI design
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