I bought premium. I was thinking of purchasing it a long time ago, but I never really did it because I thought school would've consumed more of my free time (not really).
ATLFalconsFan I think that the ads don't obscure the whole screen, they just appear along the sides and bottom, and only generate revenue if viewed or clicked. Pretty sure I read about this in the Jetpunk Tree Planting comments.
https://www.jetpunk.com/users/quizmaster/blog/a-new-tree-planting-partner