Apple first released its own battery cases for the iPhone starting with the iPhone 6S. The new $129 cases aren't all that different in concept.

The rubberized elastomer stretches back, and the iPhone slides in.

The microfiber inside keeps things scuff-free. A Lightning port inside the case docks with the iPhone, and it's connected. 

Case and phone can charge together, or the case can charge separately over Lightning or wireless Qi charging.

It's bulky. Here's the bottom, with the case's Lightning port pass-through and speaker/mike holes.

The bulge has moved down a bit from the older case's mid-body bump. The same 1,369mAh battery is on both XS and XS Max battery cases.

Charge status for the case shows up in Apple's battery widget on the iPhone.

Side profile: You'll need sizable pockets.

Both cases feel comfortable to hold, though, and protect the iPhone reasonably well.

Plugging in the case to charge on its own. So far, the case has enough juice to top off the iPhones well through the day, but the battery capacity is less than what's in either iPhone.

There's a little LED light that glows orange then green when fully charged, but the case doesn't show battery status otherwise. Read more impressions as we keep testing them.