These are playable on other iPhone 6s or 6s+ devices if you send it via iMessage, and I tested one on an iPad Air (gen 1) and an iPad 3, and both worked fine. You can also play them on an iPhone 5s or higher. If you send it to an older device, or one not running iOS 9, all the recipient gets is the still image. On supported devices, there's a small circle at the top of the photo, and you can “long tap” or tap-and-hold on the image to make it play. If you want to share with those who are not running iOS 9, or perhaps are on a (gasp!) non-iOS device, LINK that's another story.
Below is a movie showing a Live Photo, sent via iMessage to a first gen iPad Air: