Are both pics of the same tablet? It looks like the top pic is a longer ratio left to right as is shows in the pic where the bottom pic looks more like it's shaped like a regular piece of copy paper.
Same tablet rotated in Portrait and Landscape mode.
The music in the top was a half page of music like in an old fake book, and the bottom pic is a full page sheet of music.
If I had the top pic in portrait, the music would have occupied 1/2 the screen............. same size as in the fake book. Rotating to landscape filled the whole screen.
Attached are 2 more pics showing the same song formatted to original size and full screen in portrait mode.
Many possibilities for display preference. The same song displayed 3 different ways.
Jerry