Описание тега launcher
A launcher is a program that stores locations of applications to aid users in starting them.
Different desktop environments can have a variety of available launchers to aid users in starting applications in a general sense.
With regard to Android, Launcher is the name given to the part of the Android user interface that lets users customize the home screen (e.g. the phone's desktop), launch mobile apps, make phone calls, and perform other tasks on Android devices (devices that use the Android mobile operating system).
Source: Webopedia
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