That's an understatement... With App Actions and coupled with Smart Actions, you can set up apps to perform functions based on Smart Action triggers. For instance, if your wife tells you to call her as soon as you get to work (and if you're absent minded like me), you can have your Smart Actions triggered to the WIFI on your office network, which will then activate the phone call to your spouse (an App Actions Direct dial that you've set up earlier) so that as you arrive at the office it automatically calls her and then she can tell you what she needed you to call her for, and you don't get in trouble for forgetting to call.
Or you could set up a specific playlist on your Music Player (another App Action), and have it start playing as soon as you dock the phone on the car navigation dock, then have it pull up your navigation and give you directions to your preset destination (the exact method described to the OP in my earlier post). This way, you've actually triggered TWO App Actions with Smart Actions.
There are essentially an endless variety of options available as long as the App allows preset actions.