Mini LCD display for computer

Is it possible to output a computer monitor signal to a mini LCD, about 4", such as an iPhone screen. Note I am talking about the LCD screen itself, like this:

So running VGA signals to a small color LCD? Yes but almost impossible with arduino. There is not enough memory on arduino to buffer the content being displayed.

The problem controlling the iPhone LCD too, is that it is 100% undocumented, how to use it. I think it's kinda custom....

// Per.

Thanks for the replys guys, will try a different method

If you describe briefly what you want to do with this display, we can make some suggestions.