Some people say all the movement on the iOS7 operating system is giving them motion sickness. If this is bothering you, there's something you can do about it.
You can disable some of the motion features on their iPhone or iPad by going into Settings, and then looking under General, then Accessibility. There's an option there called Reduce Motion, which if turned On will limit the way icons move on their screen.
That's as much as Apple currently allows people to disable, but if there are enough complaints they may allow more restrictions in a future release.