Basically, if you look up comparisons between the Nokia Pureview and the Apple iPhone for pictures, it's a toss-up. The Pureview at best is marginally better on some things, but it is one of those things that requires close examination, not something that's obvious from a glance.
Meanwhile, the Pureview sensor must be massively expensive relative to other cameras since it's such a unique sensor size/denisty, the extra processing required (dithering from 40 mpxl to 5mpxl) slows down responsiveness, and it is physically bigger on the phone.
Meanwhile, the Pureview sensor must be massively expensive relative to other cameras since it's such a unique sensor size/denisty, the extra processing required (dithering from 40 mpxl to 5mpxl) slows down responsiveness, and it is physically bigger on the phone.