Simple, customizable, pleasant, I would be willing to pay.
Ive been using Noizio since March 2015 and find it effective and enjoyable. The typical American house or office is not quiet, with the sound of air conditioning, heating, refrigerators, vacuum cleaners, dogs barking, children playing outside, chainsaws, weed blowers, etc tending to interrupt or annoy. Nozio can cover most of those noises (except vacuum cleaners) pretty well. Im delighted that it is free, but would gladly pay. The only possible additional feature that comes to mind is a way to upload ones own sound loops. Other than that, I cant think of anything that would improve it.
TomJL about Noizio — Calm, Meditate, Sleep