Hi, I've been making some calculations. Im a fanboy and a bit too obsessed.
the thing is, iphones until now have not had an exact 3.5 inch screen but about 3.5392 inches. (ppi is 326 of iphone4s)
what i mean with this is that an exact 4 inch with 1136x640 resolution we'll get a ppi of 325.97.... and its unlikely to make an exact 4.00 inch screen.
So if apple only didnt make an exact screen size just like it has been doing until now, making, say for example, a 4.0544 inch screen, the ppi would be 322 ppi with a 1136x640 resolution, and i think it is very possible that they wont make and exact 4.00 inch screen.
Apple wouldnt let the ppi go down for marketing reasons. so i've found a possible solution to this.
a 1152x648 screen resolution is a perfect 16:9 not like 1136x640 (16:9.014) and that makes a difference... actually the 16:9.014 just feels wrong.
a 4.0544 inch screen at 1152x648 would result in a perfect 326 ppi.
and 4.0544 inches is almost exactly 0.5 or more inches larger than the current 3.5392 iphone 4s screen.
why to choose it:
So to have a better 16:9 aspect ratio i think apple would choose the 1152x648 resolution. This also would make the ppi a perfect 326 with a 4.0544 inch screen which is more than 0.5 inches bigger than the iphone 4s.
Why wouldnt they choose 1152x648? Well the only reason is that they'd have to increase 8 pixels horizontally, but i dont think thats a big problem because 8 pixels are almost insignificant at that ppi, and all that apple would need to do is zoom in the apps that werent yet optimized, this zoom wont be noticed with this pixel density, so just like what happened with the transition from the 3gs to the 4, developers will start doing apps in the newer 1152x648 and they can take their time because in the meantime the 640width app will fill the screen being insignificant the pixelation created with the zoom.
After all this make your own conclusion. 1152x648 is a perfect 16:9
everything makes much more sense... just 8 pixels cant justify changing the aspect ratio of a really respected 16:9...
--- Tell me what you think and make me any questions. And please could someone tell me what source said it will be 1136x640 and how truth or secure this is? was it just a rummor? is there any chance of a change?
By the way this is my bet, i bet they introduce a perfect 16:9 1152x648 4 inch screen (4.0544... or so) with a ppi of 326. This is one of the surprises apple is preparing for us and im shure its the best choice of screen to do for them.
--- I calculated the ppi's in this website
http://members.ping.de/~sven/dpi.html
--- iphone's screen measurements have been done with my own methods.
sorry if i didnt explain very well but english isnt my first language, again any questions or comments theyll really be appreciated.