Phones live in pockets
I think a big reason phones have a faster refresh cycle is that they live in a harsher environment. People are more likely to physically damage their phones through routine use and abuse. Also when a phone battery decays to no longer lasting a whole day people are likely to replace it. As tablets get less frequent use overall and have bigger batteries to start with, battery decay is slower and less noticeable.
Biting the hand that feeds IT
