System Performance Cont'd and NAND Performance - The Apple iPhone 6s and iPhone 6s Plus Review
Scroll half way down the page.
Samsung will always be behind until they are using a better NAND controller. Which is funny since they make some of the fastest SSD's I've ever used.
They just aren't trying when it comes to their phones.
Last year Apple's implementation made it's OS twice as fast (see results from above link) as Samsung.
I am switching to Samsung with the Note 7 but I have a ton of questions for them as a company. They fall short on certain things that they should never fall short on. They design and make their own CPU's and memory. They should equal or beat Apple in all speed tests, real life or synthetic. Instead, they are 50% slower. Absolutely no excuse for this.