launch Contact Picker
Triggers the Android system contact picker UI.
Requires RegisterContactPicker to have been called previously to initialize the launcher.
Triggers the display of the platform-specific contact picker interface.
Calling this method will navigate the user away from the current app to the system's contact selection UI.
Displays the native iOS contact picker.
This method resolves the current top-most UIViewController and presents the CNContactPickerViewController modally. It also sets this instance as the delegate.