Thought I'd make a thread where we can share thoughts, opinions and speculation on the next iPhone's screen. Let's get the ball rolling... I'd love a 4", and I think it's the only size they should go to if they are going to change it. Sizes such as 3.7" aren't different enough to warrant a change in my opinion, and anything over 4.2/4.3" to me is absolutely unnecessary, especially considering I have an iPad. 4" to me is the way to go, otherwise don't change it, although I'll probably be buying it regardless to replace my faltering 2nd gen iPod touch.
Wow, thanks for starting a thread where people can talk about this, I haven't seen any created in the last 30 sec!
Too bad you are being downvoted. I think it's really an interesting discussion and most people will just downvote you because it's not what Apple is doing right now - and Apple is always correct, of course. I recently created a post in which I came to the conclusion that if Apple were to introduce an iPhone with a bigger display (but with the same 960 by 640 resolution), the best decision (financially (and let's not forget: Apple is all about minimizing costs and making huge profits)) is to settle with a 4.3-4.4-inch display. A 4.37 inch display with a 960 by 640 resolution has a pixel density of 264 pixels per inch: that's the exact same pixel density as the new third generation iPad. Why does that pixel density matter? It's very expensive to use displays with a new pixel density. Samsung, LG and Sharp are, however, now busy with producing 9.7" panels with a pixel density of 264 pixels per inch. The infrastructure is already there, and thus 4.3-4.4 inch display would be, from a financial view, the best decision. I'm not sure what Apple will do, but I sure as hell think a 4.3"-ish display is a great size (if the border around isn't too big) for the years to come.
I don't think they will drop the dpi. The idea of a "retina" display is based on viewing distance which is closer for iPhone then iPad. But a 3.9" seems possible: http://forums.macrumors.com/showthread.php?t=1356262