Do cell phones really need a screen saver?

Screen savers are no longer necessary for modern LCD displays such as the ones used on cellphones. It is much more efficient to simply have the screen power down after a set period of time.

The point of screen savers was to prevent a common problem with CRT monitors known as burn-in. When a static image was displayed for long periods of time, it would faintly appear even when the monitor was turned off. Displaying an animation whenever the device wasn't in use was a simple way to prevent burn-in, and the function remained available on newer LCD screens, even though they are not affected by the same issue.