One of the huge differences is Apple hasn't gone down the root of making octo-core ARM CPUs. They stuck to dual-core designs all the way until (and including) t

One of the huge differences is Apple hasn't gone down the root of making octo-core ARM CPUs. They stuck to dual-core designs all the way until (and including) the iPhone 6S, then the iPhone 7 going quad-core, and the iPhone 8 going hexa-core. They've very clearly avoided following the big.LITTLE that most ARM licensees have followed.