Car alarms...a blaring stop announcement on the train...the people upstairs who sound like a stampeding herd of ponies. Sometimes the entire world seems to be in cahoots to keep you from taking a nap or having a few moments of quiet study. Binaural Beats by Rockifone, a free app for the iPhone, is a great way to block out distracting noise.
Binaural beats are different pulsating tones which are meant to be listened to in stereo, ideally with headphones. There are some claims that they induce relaxation and improve memory retention. However, more research is needed, especially regarding memory improvement. I can personally confirm that combined with ambient sound, binaural beats seem pleasant and soothing.
Binaural Beats by Rockifone provides seven preset combinations of binaurals, background and ambient natural sounds such as "Soft Tide," or "River," which supposedly promote certain mind-states, such as "Studying," or "Pre-sleep induction." You also have the option of putting together your own combination. I created a loop with the "Relaxation" binaural and the ambient sound "Creek."
The only annoying feature to Binaural Beats is that when you select the app icon, you are prompted to purchase Rockifone's deluxe
version. Fortunately, this can be skipped past with one tap. If you'd like to find out more about the fact and fiction behind binaural beats, the audiophile blog Sound on Mind provides a good overview.