Mac/Android: Plug an Android into a Windows or Linux machine, turn on disk mode, and your phone is basically a drive. Plug into a Mac and you get a warning. Google's own utility fixes that.
The big "if" clause is that you have a device that's running at least Android 3.0 or above (meaning Honeycomb, Ice Cream Sandwich or Jelly Bean). That's about 13.3 per cent, as of this writing. But for those who are on these versions, Google's own Android File Transfer utility is a simple, useful app for transferring files between your Android device and your Mac. Media sync apps, such as doubleTwist and other Mac/Android solutions, involve far less click-and-explore, but for those wanting simple access to pictures, music and files, this is the best option. Install the app, and whenever you plug in an Android phone over USB, the app window will open and interact properly with your Mac's own Finder windows.
Android File Transfer (for Mac) [Android]