Just announced at the September 2015 Live Apple event that the new iPhone 6S will be able to take 63 megapixel panorama photos and will also come with a new 5MP FaceTime camera on the front side which may also be able to take selfie panoramas - we wait to see!
Update 09/25
We've just taken and printed our first photo on the new iPhone 6s Plus camera and it's a beast! We managed to get 16374 pixels wide by 3866 pixels high which is 63.6 megapixels wide and at 36" is an insane 454 pixels per square inch!