[Zubersoft]

It's definitely related to the aspect ratio. A4 paper is closer to a 4:3 ratio so it will make better use of the screen space. You have a couple options for how to utilize the 16:9 aspect ratio tablet better. One is to crop the music to remove margins as much as possible so the music can be stretched better to fill the screen. The other is to change the page scaling mode so that the music is stretched to fill the entire screen. This can work well if it's only stretched a small amount, but if it's stretched a lot, you will see some distortion in the image.

Mike