2 Different A9 CPU's
 

http://www.kitguru.net/apple/matthew...-manufacturer/

Might be a bit of a gamble which one you get and how good your battery will be.

Apple will surely deal with this under QC but a bit annoying for them as clearly one plant isn't delivering to their specs.

I can't not focus on Samsung being the **** chip. It's a bit rubbish if you have the Samsung, but no doubt the Samsung is to spec and the TSMC is over delivering.

It makes sense that a 14nm chip should generate more heat for a given amperage but it should be more efficient and use less current. it makes no sense really unless it's sabotage?

Mind you running a cell to lower than 20% is going to seriously damage it's lifespan and capacity no matter what the phone or chip.

I doubt it's sabotage, but it would be fun if it was.

And commercial suicide :)

I can't see the smaller process chip being the under performer, something is amiss.

Might be down to the 16mn chip being more optimized in the software department.

We all know the smaller fab should be the cooler and faster, something isn't adding up as Samsung's fab have been spot on this year if anything.

Edit - Seems quite a few with the samsung chips are happy with performance, and they run cool.
Either someone's telling porkies, or someone has a duff phone.

The fact there are two chips is still a bit rubbish.

Is a bit, more than likely tmsc's output isn't enough so had to go back to samsung to cover the additional required.
Not ideal as you know Apple are trying to remove themselves from samsung, as using them they are shooting themselves in the foot a bit.
Must be a pain for software devs, having to cater for two different chips, let alone any performance differences.
It's a shame because device wise it's nice and for me the first decent apple device specs wise in a long while.

There's no additional coding. I want one too, 3D Touch is outstanding.

The comments below just aren't believing apple. Remember 'antenna gate' and many others

You're holding the phone wrong 😨

I do remember it, I owned the phone and was holding it right.