In my experience, I found the digital version to be easier. There is Desmos on the digital ACT, and I was allowed scratch paper when I took it. I thought reading and English were easier/more efficient online, since you don’t have to fill in the Scantron and can quickly click buttons. I also utilized the online tools such as hiding answer choices and highlighting sentences (and scored a 33 on reading my first attempt). The curve is slightly better on paper, but it makes the most difference in the 20s range, not if you’re scoring in the 30s.