Chatterblocker, as its name indicates, is intended to block out sounds so that you can concentrate. It works super well with the desktop version, and I was thrilled when it came out as this iOS version. I had been using a hour-long recording of my desktop Chatterblocker before as a way of using it on the go, but this is the real thing. I dont habitually use it to block out sounds (although it does that well). I tend to use it to help me concentrate. Its often better than background music because Im not trying to not pay attention to the music. Its a lifesaving app!
lucenvoyage about ChatterBlocker