Enhancing Productivity with Specific Apps (OS X, iOS)

I'm a college student owning a MacBook (End 2008 with Lion on board), an iPhone 4 and an iPad (second generation). I bought the iPad for college to make my bag lighter in weight, while being productive in note taking and have some entertainment between classes. But I recently started to take my laptop to classes again, because note taking and doing research is so much faster with a physical keyboard.

What I wanna know from you is, how do you use your setup in terms of organization and productivity? Which apps do you use? I currently struggle to have a working software setup that leaves me satisfied with my workflow and does not distract me. I hope some of you have some tips!