About 2 years back, I read this article on Michael Degusta's personal blog. It was a revelation. Michael ripped the Android ecosystem apart with a simple chart. The chart converted me from an Android user to an iPhone user. I hope this chart helps other folks make an informed decision when their next smartphone upgrade is due.
Charts like this do great in certain areas of the web, but it's too simplistic. First, it does not take into account that many core aspects of Android are updated through Google Play, such as Chrome, Gmail, Maps, the keyboard, and so on. Whereas iOS needs an entire update to fix a small bug in, say, Maps - Android does not. Many core parts that require an entire OS update for iOS are updated weekly on Android.
Second, it does not mention that even though older iPhone models get the latest version of iOS, some functionality of these latest versions is disabled due to marketing, and in some cases due to hardware constraints (if you were to believe Apple, that is).
Third and foremost, though: I'm betting each and every one of those devices has at least an Android 4.2 or 4.3 release (and some have 4.4 too, like my Find 5) from, for instance, CyanogenMod - and countless other ROM makers. Installing a custom ROM is one of the strengths of Android, and not nearly as hard or difficult as some make it out to be. If your iPhone becomes unsupported or really slow due to iOS7 - you're screwed. You have no other options. If Samsung's TouchWiz crap makes your Galaxy slow,
run out and get a quality phone install a custom ROM.
I see this all the time: people ignoring core strengths of Android because they don't understand them or because they don't belong to their interests - "this is just for nerds and geeks, so it's irrelevant!" Take discussions about application on iOS and Android, for instance; those arguing in favour of iOS routinely ignore that Android has access to types of applications iOS users could only dream of. If you leave those out, it's easy to make Android's application offering look weaker. The same happens when looking at Android and updates.
All this doesn't negate the fact that updates are by far Android's weakest link, although not nearly as much of an issue as it used to be during the gingerbread days. Moving more and more parts of Android to Play will eventually all but solve the issue completely.