Slick Moto X Camera App with Gesture Control Exposed in Leaked APK
(Image credit: Android Police)
Obviously, there are limitations, as the software is designed for use on the Moto X’s hardware, but apparently the software will run on a Nexus 4 with Android 4.3 as well as a Samsung Galaxy Note II with Android 4.2.2.
The camera works, it’s possible to take single and burst shots as well as shoot video, and the tutorial is there. Controls including front-to-back camera toggling, swipe to open, touch to focus, flash mode, toggling the shutter sound on and off, and geo-tagging are all present and working, as well.

(Image credit: Android Police)
The intriguing wrist double-flick feature doesn’t work, though, and HDR mode and slo-motion mode can’t be enabled; the panorama mode crashes, too.
Unfortunately, it appears that downloads are now disabled, so you can’t play with the APK yourself, so we’ll have to settle for a description and some photos to tide us over until the Moto X finally makes it debut.