So much for the screen. We’ve learned that Google's revamped Google Glass project, dubbed Project Aura, is working on a wearable with a screen—and at least one without.

People tell us there have been three versions of the head-mounted device in development, although the three may be consolidated into two. One version, targeted at enterprises, has a screen. The others, one of which is targeted at "sport" users, doesn't and relies on audio. They use bone conduction, like the original Google Glass. In other words, headphones worn on your face.

Project Aura overseer Tony Fadell experimented with head-mounted designs at Apple eons ago, which is probably one reason he’s running the project. We hear the team, which includes audio experts hired from Amazon.com, is still targeting next year for release.