iPhone XS and XS Max in silver, space gray, and gold.
Apple Claims TSMC vs Samsung A9 Chip Variants Result in Only 2-3% Difference in 'Real World' Battery Life
In a statement given to TechCrunch, Apple says that it has done internal testing and gathered customer data to determine the performance difference between the two chips in the iPhones.
With the Apple-designed A9 chip in your iPhone 6s or iPhone 6s Plus, you are getting the most advanced smartphone chip in the world. Every chip we ship meets Apple's highest standards for providing incredible performance and deliver great battery life, regardless of iPhone 6s capacity, color, or model.Apple says that early battery benchmark tests conducted by customers, such as those we shared yesterday, are not reflective of real world usage conditions. The two to three percent difference that Apple has seen in data gathered from customers is "well within its manufacturing tolerances" and is a level of variation that could be seen between two devices with the same chip.
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.
Apple's statement on real world usage reflects what recent YouTube tests have revealed. Side-by-side battery tests comparing a TSMC iPhone and a Samsung iPhone did not show differences as dramatic as benchmark tests have shown, but those videos are also not quite indicative of real world usage results. On the MacRumors forums, opinions on battery life have been highly mixed. While some users with Samsung chips have reported poor battery life, others have not reported issues.