Can you delete mobile apps from your computer to save space

Hi all,

A few years ago I deleted all the movies off of my Macbook Air to save space. I'd like to do the same with my mobile apps. I haven't had any issues downloading movies to my iPhone or iPad as needed, so I'm hoping the same will be true for apps. Is there any reason to back them up on my computer in addition to iCloud?

Thank you!

Jenn