I have been searching and I didn't find an optimal solution for my problem. I have some apps purchased from the Mac App Store (Pixelmator, GarageBand), and other ones installed (Xcode).
I want to know is there an efficient way to backup this apps, and reinstall them after I do a fresh install of my system.
P.S. I want to do this because Xcode's download size is too big, and my internet connection isn't the better around... Same with other apps.