Although the inside of the iPhone 4S contains some major differences from its predecessor, the exterior of the iPhone 4S looks exactly like the iPhone 4.
As Mashable’s Amy-Mae Elliott pointed out last week, that means mostiPhone 4 cases will work just fine with the iPhone 4S.
Still, in the run-up to Friday’s launch date, we’re seeing a lot of conflicting information about what cases and accessories will and won’t work with the new iPhone 4S.
The iPhone 4S does have a few minor design changes from original iPhone 4. Notably, the mute switch and the two volume buttons have moved ever-so-slightly to accommodate a new antenna. Eagle-eyed iPhone fans will recognize these changes from the launch of the Verizon iPhone back in February.
Although most iPhone 4 cases will still work with the Verizon iPhone 4/iPhone 4S, cases that were designed to specifically mold to the side button layouts may be slightly off.
The good news is that over the course of the last eight months, the vast majority of case makers have updated their molds to account for the new design. Most simply have an elongated rectangle on the side of the case to account for the buttons. A few have gone as far as to create specific button holes in cases for Verizon iPhones.
What this means is that if you purchased a case for your iPhone 4 within the last six to eight months, chances are, that case will fit the iPhone 4S. For users who got a case or bumper when Apple launched the iPhone 4 in June 2010, the situation is slightly more complicated and you might want to bring your case with you when standing in line to get the new phone.
Still, the cases sold alongside the iPhone 4S in Apple Store in the U.S. and across the world should be fully compatible with the iPhone 4S.
And for the super-paranoid, we’ve already put together a list of some iPhone 4S-friendly cases.