I actually took many hours this morning to find out how to do it, but I want to see alternatives to it.
I got my iPhone in sync with my iTunes at home, my first machine. I could "just" bring the app folder/file back home and sync through that. It works just fine.
The question here is on alternatives to that. Jailbreak or not, how could we do it on a second machine?
edit: I mean to install an actual file like application.app or application.ipa just like they are on the
Mobile Applications folder or on iPhone's own