Has anyone looked at this device under a magnifying glass or microscope to confirm how many PPI the 6s is? I wonder if they'll bump it up to the proper no-scaling @3X 1125x2001? I didn't notice a big sharpness difference between my 6 Plus display and my older iPhones, but I wonder if the same is true when I go back down in size after getting used to it. When using my iPad or rMBP I don't notice them being lower PPI—but I also use them from further away.
As for the physically larger A9 chip, I'm hoping that they either added an extra core such as the A8X in the iPad Air 2, or they've added additional video cores. The latter would suggest that they might have moved to @3X for the display. I suppose it could be for the extra RAM, but I think that after three years they could just use a denser chip in place of the 1GB module, correct? If this A9 chip is 10% larger, and their new process is 14nm, then that's 30% smaller than the 20nm process. For reference, the A8 chip is about 30% smaller than the A8X chip—at least according to some numbers I found in a quick search. So either this iPhone is going to be freakishly fast (extra cpu and/or video cores, have amazing battery life (more integrated chips), or a mix of both (I think this option is likely). But significant improvements should be seen if their 14nm process results in a larger chip. Someone please correct me if I'm way off base with that assumption!
I'm looking forward to these energy efficient chips. My iPhone 6 Plus has plenty of battery life, but that is my only meaningful concern with going back down to a smaller iPhone. I hope they are also able to squeeze a few hundred extra mAh into the new battery design. As I mentioned above, the 14nm process should really help as well—as long as they don't put all of their design budget into speed. Overall this should be a solid upgrade that is much more significant internally.
