As well as random turn-offs (iPhone Owners Complain of Random Shutdowns), the iPhone 6S is said to be suffering from battery life problems – which can be traced back to the chip.
There are two versions of the phone. Although both use Apple’s A9 SoC, these are made by two different companies: one is a 16nm TSMC device, and the other is a 14nm Samsung chip. Tests have revealed that the battery in the TSMC model can last up to two hours longer.
Apple has commented on the claims, and says that while there is a difference, in real-world situations it is actually much lower than the tests show:
“Certain manufactured lab tests which run the processors with a continuous heavy workload until the battery depletes are not representative of real-world usage, since they spend an unrealistic amount of time at the highest CPU performance state. It’s a misleading way to measure real-world battery life. Our testing and customer data show the actual battery life of the iPhone 6S and iPhone 6S Plus, even taking into account variable component differences, vary within just 2-3% of each other”.