Thanks to my current job, I'm in front of my computer for hours during a normal work day and on my Android smartphone when I'm in the service bay taking photos of bikes or searching for information online for the techs. In that time, I've been introduced to quite a few useful (and FREE) online services for both my phone and the PC that have increased (or if I'm at home, decreased) my productivity. Here are a few that some of my friends have directed me to that have become commonplace on all my machines.
Note: I own an Android so I'm not sure if some of these apps are available for iPhone.