During the day at home,I use my laptop mostly, but when I go to bed, it became usual to spend up to an hour using my ipad, then again when I woke early. Then came headaches. I put it down to rapid eye movement. Using the laptop requires focusing as pages move one way, then with ipad,movement is different. I suppose I should add that I am mid 70's. So, apart from short bursts during the day, the ipad will remain unused. If headaches clear, then I know it was that. One thing I will do, is change settings to reduced power which I believe will reduce glare.