It doesn’t do much — no fancy vocal wizardry, just adjusts the pitch of the user’s voice up or down — but Devil Voice looks like the first instance of a real-time voice-changing app, without the need to record a user’s voice first before playback — though it can, if desired.
The app is a dollar, and comes out just in time for Halloween; see our forthcoming Halloween Guide for examples on how to duct tape it and attached speakers into a Darth Vader mask and whatnot.