Case-in-point, what new features is 4.3 bringing to the table? Hasn't Android begun to slow down as well? I think we're just seeing a maturing of the smartphone industry. Apple and iOS started out more polished, while Android was kind of all over the place and didn't really hit its stride until ICS - longer way to go = more growth. And good for them! I for one am happy to own devices that run both iOS and Android. I enjoy different things about each.
I'm sorry but it's not an apt comparison.
Android at this point is more feature-rich, more mature, more flexible OS and there's really only so much more they can do. There's absolutely room for improvement, but not as much as iOS could and should go.
Case in point, what more can we expect of Google Maps? Can it improve? Of course. But how much more does it need to improve compared to say Apple Maps?
Google is constantly updating their individual apps too. Recently, Google Keyboard, Gmail, Chrome (Beta and regular), Maps, Music, Translate all got updates. So to pretend like the OS updates don't add a lot comparatively is obscurantism at its best.
In short, iOS has far more room for growth at this point in time.
This is similar to the argument that the S4 isn't a "big jump" from the S3. It's just not the same. Once again, Samsung simply has their bases more covered.
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I said this before...
No other company would get away with pulling the same things that Apple pulls.
Imagine for a moment if it was Samsung (or HTC, Motorola, whoever) that all decided to stay with a 3.5" phone for four or five years. And imagine if it was Apple that offered 3.5", 4", 4.3", 4.5", 4.7" and even 5" phones as the years went by? The arguments would be completely flip-flopped and every Apple fan would destroy and ridicule Android OEMs to no end for sticking it out with 3.5" phones.
And this is just using one example. Imagine if Android OEMs stuck with one hardware button, while Apple moved onto capacitive and/or on screen buttons. Imagine if Apple offered SD expansions and Android OEMs refused to? Or notification lights while Android OEMs refused to?
Imagine if Apple allowed the freedom to customize the OS, to make apps default, to share files to anything, to have full attachments, to have multiple methods of typing, etc. (these are just some examples)... all the while Google refused to implement those things in Android.
Really, try to imagine how the conversation would go if all the tables were turned.
I'd be an iPhone owner, too, and I, too, would laugh at Google and their partners if all this was true.