Copy and paste in iPhone works even if you quit the app you're pasting from and open a new one.

Copy and paste in iPhone is universal, or about as close to that as it needs to be. It works on essentially all text, and basically the same way in all places. In contrast Android copy and paste is much more selectively available. It is often hidden in menus that are different from application to application.

Copy and paste is one of those things that has to be done the same way everywhere to achieve its height of usability. My Nexus One does not live up to my standards for that.