I have an iPad 2 which I use a clear TPU case to protect its back. I have been putting this iPad 2 (with the TPU case) into my original Apple iPad sleeve/folio case, which fits perfectly. When I took out my iPad 2 today, I was shocked to this that the back of my iPad 2 (with the TPU case) has many blue discolored markings, part of which appeared to be traced from the outline of my original folio case (including the part that holds the iPad up). I am attaching a photo here for your viewing. I have been unable to find any other similar reports. Some reports say that that may be slight yellowish discoloring of a TPU case over prolonged sun exposure (I have been keeping my iPad 2 indoor), but no reports of a blue discoloring. Can someone explain what is happening? Can this be fixed?