I'm surprised there are not phones with two batteries that do this (one for 2g calls etc. about 2 weeks and one for 4g/Apps/Etc.). I guess the battery costs of

I'm surprised there are not phones with two batteries that do this (one for 2g calls etc. about 2 weeks and one for 4g/Apps/Etc.). I guess the battery costs of the screen are too high to bother, leading to a modest 2 day calls only, 1 day full phone situation... it's still not a bad idea in some ways, but might mean that you could never say you have run out of battery...