A one-line description used by the device to identify the app for the user.
On Android the titles appear above the task manager's app snapshots which are
displayed when the user presses the "recent apps" button. On iOS this
value cannot be used.
CFBundleDisplayName from the app's
referred to instead whenever present,
To provide a localized title instead, use onGenerateTitle.
This value is passed unmodified to WidgetsApp.title.
final String title