Yes, Live Photos can be captured with the FaceTime camera on the iPhone 6s and iPhone 6s Plus. The front facing selfie camera was upgraded to 5-megapixels and is capable of taking Live Photos, just like the main iSight camera on the back.
Taking a Live Photo with the front iPhone camera requires the Live Photo toggle to be enabled.
Yes, Live Photos record sound while they are recording movement. The data collected before and after the shutter button is pressed includes approximately 1.5 seconds of sound.
Playback of the sound in Live Photos is possible on iOS 9 devices, as well as Apple Mac computers running OS X El Capitan (10.11) or later.
Mac computers running OS X El Capitan are capable of viewing Live Photos that have been captured on the iPhone 6s and iPhone 6s Plus. The El Capitan (OS X 10.11) release date is September 30.
Other Apple devices will also have the ability to view Live Photos using iOS 9 or later.
Live Photos can be viewed on Apple devices running iOS 9 or later, however they can only be taken starting with the iPhone 6s and iPhone 6s Plus.
Older iPhone models will not have the capability to capture Live Photos, only watch them move.
Apple described Live Photos as 12-megapixel still images with data captured before and after the shutter button is pressed. Apple utilizes an "Efficient frame-to-frame technology" to store the additional movement.
Further information reveals that Live Photos combine 3 seconds of video (1.5 seconds before and after the still is captured) with the 12 megapixel image. There are 45 frames saved, equivalent to 15 frames per second.
The combined Live Photo file can take up almost twice the space as a single still image captured at the same resolution.
