frozen

My wife's kindle app on her iPad Air2 is frozen on a book page and completely unresponsive. I decided to delete it and re-download from the App store but I can't delete it. Usually when I select and hold an app, a small x appears on its corner and I can the click on that and select Delete...

First let me say that I have no experience with Apple products, nor am I all that technically savvy about computers. Recently my goddaughter asked me to help her with a problem she was having getting her Ipad 4 to charge. When I first saw it the screen was black and it would not turn on. I...