2 AnandTech | Apple iPhone 4S: Thorough

History loves to repeat itself, and even Apple isn’t immune to the yearly cycle of rumor and release. Leading to each year’s iPhone refresh, excitement, rumors, and hype build to a fever pitch, features and designs are added into an increasingly unrealistic combination, and finally everyone is silenced at the device’s eventual unveiling.

Today we’re looking at Apple’s latest iPhone refresh, the iPhone 4S (henceforth just 4S).

The review has to start somewhere, and the path of least resistance is usually just exterior appearances - in this case the 4S is easy to go over. The 4S keeps the overall form factor and design of its predecessor, but to call it identical to the iPhone 4 isn’t entirely correct. Instead, the 4S borrows its stainless steel band break locations from the CDMA iPhone 4, which we talked about extensively when it finally released. The GSM/UMTS iPhone 4 previously had three notches, where the CDMA iPhone 4 and 4S have a total of four.

The long and short of this change is that the notches have been moved around to accommodate a design with two cellular antennas. One is up at the very top, the other is at the very bottom - the two are the small U shaped portions. The result of this change is that the 4S has a very symmetrical design, as opposed to the GSM/UMTS 4’s asymmetric layout.

Just like the CDMA iPhone 4, the 4S also moves the vibrate/lock switch down the device just slightly to accommodate the new break for the top antenna band. This is the physical change that breaks compatibility with cases designed for the older GSM/UMTS iPhone 4. If you recall previously, however, Apple refreshed its bumpers with a new “Universal” line around the time of the CDMA iPhone 4 launch. At that time, case makers also followed suit with a larger vibrate/lock switch port. The result is that if you have a “universal” case created after the launch of the CDMA iPhone 4, you likely won’t need a new one for the 4S.

I say likely because some cases that cover the front of the 4S and are universal might not work as well owing to a small change in the placement of the 4S’ ambient light sensor. It’s going to be a case by case basis to determine which 4 cases that cover the front of the display work with the 4S.