Right, if you want to talk about screen sizes.........
With Android I have always been of the belief that it needs a big screen, because then you can use those widgets etc. iOS doesn't offer that so it works great with a small screen.
I was able to use my iPhone 4 quite happily, but I can use my Nexus 5 happily too, both for the reason I said. I do have bog pockets though so my Nexus 5 disappears as much as my iPhones used to.
But people want a bigger screen, I carry my Nexus 7 around, like you carry you iPad Mini, because to me they offer the best of both worlds as you get a proper big screen yet they are easily portable.
Now, many ask for a bigger screen iPhone, but what are they going to do on it? Because if your talking reading or playing games, a tablet is still better.
I was happy with my iPhone and only switched to the Nexus 5 because I hate iOS7, but size wise, as I had my Nexus 7, an iPhone was fine.
I actually hold the iPhone 4 as the best iPhone I ever had, and if iOS7 wasn't the mess it is, to me, then I may have just got an iPhone 4S. Because I feel they were better built then the iPhone 5 I had.
I've actually posted in these forums that I hope/think Apple will release some unique features for a larger iPhone and the iPad eventually. Something that differentiates the segments other than simply the size.
Perhaps this is that year because of the release of larger screen offerings? I don't know. I do know that whatever they do - I'd like as much screen in as small of a device as possible. My sweet spot would likely be a device with just about the same dimensions as the 5S, but with a larger screen and the design of the iPad mini/Air.
Not sure how much more screen they could squeeze in their - my guess is only .3" at the most. But I don't think a 4.7" iPhone is going to physically be much bigger than the current iPhones. And I think if they put out a 4.7" AND a 5.5" version - the 5.5" will get SOMETHING that sets it apart.
I don't know what that is (though I would say with near 100% certainty, it won't be a stylus or "s-pen" like tool), but I'll bet there's something.
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I like HTC - but I think Samsung has their camera software down much better. I'm not a fan of HTC's camera software at all. Which is unfortunate because it was one of the major deciding factors for me. I don't love all the extra bloat on Samsung devices (especially since a lot is duping of Google's services) but their camera software is superior (in my opinion)
HTC's camera was the one thing that kept the One from being the perfect Android device, IMO.
From what I've read, they're adding a 13MP shooter this time around. Add that, keep the same overall design but thinner and they've got a winner IMO.