A major distinction between a desktop computer and a mobile OS such as Android is the way people interact with information on the display. A desktop offers considerably more screen real estate (even more so with multiple monitors) than is typically offered on a mobile display. As such, running dozens of windowed applications on a mobile device isn’t very practical. Yet the power of a multitasking OS such as Android allows for many programs to be running at the same time.

Android has solved this constraint somewhat with the creation of widgets. Widgets are small graphical applications anchored to the home screen that can display data in a space as small as a single icon or expand to take over most of the screen. In this section, we’ll ...

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