One of the big questions people have asked about the iPad is related to books and using the device as an ereader. Many fear that the iPad's screen is far too bright for reading for long periods of time. The Kindle and other similar models of ereader use e-paper displays for this very reason.
iPad owners will likely tell you reading on the device is quite actually comfortable, however, new information indicates that it could disrupt your sleep cycle. The LA Times cites sleep experts who say the light emitted by the iPad's bright tells your brain to stay alert. The same is true of bedside lamps and televisions but the difference is that your iPad is not just sitting next to you or across the room; it's right up in your face all the time.
Frisca Yan-Go, director of the UCLA Sleep Disorders Center in Santa Monica, told the LA Times that really, you shouldn't be playing with light-emitting gadgets before bed.
"The take-home lesson is that insomnia and electronics gadgets emitting light should not [be] mixed before bedtime," he told the paper in an e-mail. "Kindle is better for your sleep," he said later.