I was hoping for even just a slight improvement in battery life- but according to the Apple website it says the iPhone 6s has the same battery life as the iPhone 6, even though it has been reported that the battery size is smaller. This has been attributed to improvements in other technologies inside the processor (and possibly other things). Here's my question (or theory). Both phones are listed as having 10 hours of battery life- BUT what if the iPhone 6 has 10 hours of battery life on IOS8, but once upgraded to IOS 9 it actually has 11 hours. That would mean the iPhone 6 actually has a longer battery life than the 6s. What are the chances I am correct with this?