iPhone 6s' Battery Is Smaller, But It Might Not Matter
As the iPhone 6s is revealed, so too are its parts meticulously examined by the public. In this case, the battery has appeared in one of Apple's own videos, complete with a note on how large it is. While Apple doesn't generally share the mAh capacity of their batteries, previous teardowns have revealed the size due to regulation requirements for capacities to be printed on all such lithium ion units. Today we find that the battery in the iPhone 6s is smaller than that of the iPhone 6.
The new iPhone 6s has a battery that's 1715 mAh large. The iPhone 6 has a battery that's 1810 mAh large. It's been suggested that the new version of iOS, namely iOS 9, will include battery optimizations that'll allow longer life for the handsets and tablets it'll be included on.
It's also been implied by Apple that the newest hardware will be optimized for low battery consumption, allowing a smaller battery to work with the same amount of battery life as its predecessor (with a larger battery).
The new iPhone 6s works with a new piece of hardware to allow for Apple's own "3D Touch" (aka a new version of Force Touch as it was previously entitled). This piece of hardware is Apple's Taptic Engine, and it takes up just a bit of space near the battery in the iPhone 6s.
If you're watching your battery life VERY closely, you might be lucky enough to find some extra life in your iPhone 6 once iOS 9 is released. Whether or not it'll be more than the iPhone 6s, we'll just have to wait and see.
VIA: MacRumors