Battery life differences observed between iPhone A9 chip makers


Apple Statement to Ars Technica on A9 chips

"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.

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."

I think that last part is key. Apple sources a number of components from multiple manufacturers, so pinning any variation on this chip alone might not necessarily correlate to the manufacturer. However, while the causation may be difficult to pin point, perhaps there could be a configuration of components that result in a significant variance and the A9 fabricator could be an indicator of such configurations. Or it could be the chip. Or any number of many variabilities.