All iPhone 7 cases work on iPhone 8 devices including the Smart Battery, though Apple isn’t officially stating compatibility. Likely to avoid folks trying to mix the case and wireless charging that the phone supports, but not the case.

And agreed on wishing they’d open the Lightning charging spec a bit more, even if it’s only via their MFi program. It feels like Apple is trying to balance their conservative views on safe battery charging/usage and have been wondering lately if that factors into their proper adoption of USB-C on the Mac side only (lower volume) vs sticking to Lightning on the iOS side of the hardware house. If anything, the iPhone X could have been the transition point had they felt it was the time.