Fastest phone is the one with the most optimal software, OS and compiler software.
er, not quite. Hardware is still very important and Apple has very good hardware. The CPUs in the I-Phone 5 are pretty much on a par with other phones but it has 3 GPUs which puts it head and shoulders above the rest in graphics benchmarks.
But it also matters what you're testing for: web page rendering needs good single-thread performance which is why Apple again but also x86-based systems come out top.
The compiler is important but to pretend that Apple only use GCC when they have contributed heavily to LLVM, CLANG and OpenCL is worse than disingenuous. In fact being able to shift workloads so effectively onto the GPU is one of the things which makes Apple devices so impressive in the power/battery life comparisons. Microsoft is late to this particular party and Intel doesn't do GPUs that come anywhere close to PowerVR, Mali, nVidia, etc. in power/battery life.
I don't own, and don't intend to own, an Apple phone or tablet but I'm prepared to recognise classy hardware for what it is. As it stands the I-Phone 5 is possibly 1 generation ahead of the competition (better GPU performance and power/weight ratio). I don't expect that advantage to last more than six months but that has never really matter to Apple's customers.