Well, most articles suggest the difference is rather small. Heck, sometimes you also get a 2-3% variance from two similar chips. Don't quite see what the big fuss is all about...

The publication took two T-Mobile iPhone 6s units with different A9 chips running iOS 9.0.2, matched each and every setting on both phones, placed them within a Radio Frequency Isolation chamber to block out stray signals and subjected them to cellular and WiFi usage tests.

The cellular test, which involved constant transmission at “+10 decibels per milliwatt (dBm) on the  same channel in the commonly used Frequency Band 5,” showed a difference of less than 2% between the duration the two iPhones stayed powered on, with Samsung one having 2% less battery than TSMC.

The WiFi usage test followed suit, with results showing less than 1% difference in battery life after 11 hours of downloading the same webpages using a custom app and playing a collection of the same 10 songs on a loop. Surface temperature readings for both phones were taken throughout the duration of the second test as well, again, showing a difference of less than 1%

Needless to say, owing to the countless variables in play here, results might not be the same for all possible usage scenarios, but as the verdict from Consumer Reports goes, these findings are enough to dismiss any notions of the A9 chip’s make being responsible for reduced battery life.

In a nutshell, if you’ve been cursing your luck for getting an iPhone 6s with the Samsung A9 chip, you can stop now.