android:visibility, which controls whether the widget is initially visible
2. android:nextFocusDown, android:nextFocusLeft,
android:nextFocusRight, and android:nextFocusUp, which control the
focus order if the user uses the D-pad, trackball, or similar pointing device
3. android:contentDescription, which is roughly equivalent to the alt
attribute on an HTML tag, and is used by accessibility tools to help
people who cannot see the screen navigate the application — this is very
important for widgets like ImageView