press and hold that app until it's like shaking and has an x in the top left corner. if you press the x you can delete the app and just keep holding the app with your finger and move it around so you can put it somewhere else. plus if you put it over another app you can make a little file (just not the bookstand thingy i dunno why)
touch it with your finger until it starts jiggling and slide it towards the edge of the screen. Hold it at the edge of the screen until it slides onto the next screen. It takes a second so hold it there until it does.