Settings > General > Accessibility
turn Whit on Black to the on position.
Or you could also set your tripple-click on the home button to change back and forth between regular and black/white.
Not good idea I think. It would hurt your eyes and your iPad, especially in the direct sunlight. So get a sun unbrella?
can't get one. i'm new to site so bear with me. any ideas for sun screen if umbrella not an option?