As you can tell from the image above, the main different is the camera cutout what has been redesigned to fit the iPhone X, Xs, and Xs Max. The battery bump has also been “lowered” where it doesn’t stick out in the middle of the phone, but rather towards the bottom of it, but otherwise it doesn’t seem to be too different from the back.
One of the main changes, based on the icon’s design, would be to the front where Apple has removed the “lip” of the battery case to give it a more streamlined look. Previously it was unclear which iPhone models the new battery case would support, but 9to5Mac points to three model numbers: A2070, A2071, and A2171, all of which seems to suggest that there could be a case for each of the new iPhones.
No word on what the battery size will be or how much it will cost, but given the previous pricing of $99, we imagine that the new models probably (and hopefully) won’t stray too far from that range.