The only real differences between Mac OS and iOS versions is the interface. The underlying program itself runs the same. You can also potentially run larger patches on a computer because most computers are more powerful than iOS devices. However, unless you’re running really high polyphony analog-modelling patches with lots of effects, you likely won’t have a problem on iOS.
Some editing capabilities are a little faster since you have copy/paste/cut on computer on keyboard, but you also have a more fun and immediate experience with turning knobs on iOS. If you had to get only one, I’d suggest computer, but if you want to have the option to be more mobile, or you want to use it on both your iPhone and iPad since it’s available for both with one license, I’d say go iOS.
Let me know if you have any other questions!