As anyone who works with audio for a living can attest to, the human ear frequently plays tricks on the mind. For example, is it really possible to hide secret messages inside music recordings? If all things audible fascinate you, then you’ll love a new iPad app dedicated to demystifying this and other “auditory illusions.” The San Francisco-based Exploratorium recently followed up their debut Color Uncovered app with a new offering called Sound Uncovered. The free iPad-only app is billed as an “interactive book,” which allows the user to participate and learn from all kinds of acoustic phenomena around us that’s equal parts fun and educational.

We have dozens of ways to take notes on our iPhones, and while some have exquisite, minimal interfaces, others are feature-rich powerhouses that try to mimic desktop functionality on a mobile device. Write for Dropbox wants to be everything at once, and it comes as close to succeeding as any app we've ever used. By utilizing a nifty three-panel interface – with a tool bar, document list, and main writing window – Write deftly uses every inch of real estate at its disposal, with oodles of sharing options and one of the most powerful virtual keyboards we've ever used.

For many, the prospect of "inbox zero" seems impossible – the unicorn of modern communication. Mailbox understands this struggle to stay atop the constant deluge of digital correspondence, and sees the problem not as a matter of personal effort, but rather perception. As such, rather than resemble typical mobile email options, Orchestra's new iPhone app takes its inspiration from the to-do list, challenging users to clear their inboxes like checking tasks off when completed, with a handful of breezy actions used to facilitate the process.