Smartphones are, by their nature, iterative products. But if you've felt that this iteration has started to slow a bit in the last few years, you're not alone - and you're probably not wrong, either.

Think about it: smartphones have a pretty set list of characteristics and features we evaluate in order to judge the overall quality of a device. Some are more subjective than others - design, for example - but many are also quite objective, even if quite difficult to measure objectively sometimes. How fast is the phone? How long does the battery last? How good is the camera [at night, for video, in slow motion, etc.]?