iOS: Awareness funnels in outside noise over a certain threshold to your headphones, while you listen to music on your iPhone. That makes it perfect for joggers that want to stay alert to oncoming traffic, people waiting in a doctor's office that want to hear their name called, or any other situation in which your music might drown out your surroundings.
Just set the mic and volume threshold in the app, hit the power button, and you're good to go. It will funnel in any outside noise that reaches that level, so you can hear it while you listen. You can also set it to just vibrate if you so choose.
It's a very, very cool idea, and worked surprisingly well in our tests. It's usually a hefty $8.49, but you can grab it today for free, so even if you're a tiny bit curious, get it while you can.
Awareness is a free download (right now) for iOS only.