It's also deceptive to say "iOS needs a whole OS update to update things like [...]", it needs an incremental update, which it gets, so how is that an issue at all? That you can't update them individually?
Some of my relatives who took my iPad 1s when I bought new Ipads for my kids are stuck on iOS 5.1.1. Those iPads are from September 2010, but stopped receiving any updates for system apps as of May 2012.
So yes, granular, loosely coupled updates are better than "rebuild the whole tightly coupled world and ship a firmware-diff" updates.
In particular, if an app is not tied to specific kernel features on Android, changes are it can have along life, because Android OS level services like Google Play Services can be independently updated as well.
My iPad 2 (just over two years old) is a real pain with iOS7, virtually every time I switch apps the app has to restart from scratch
Still, I have zero issues with iOS 7 on my iPad 2 and my parents are happy on their 4S.
The issue there is that for someone living in a country where data is expensive, a 10MB download is better than an ~800MB one every time there's some bugfixes/app updates. Plus from my knowledge, Play Store can deliver a patch of the app, instead of downloading the whole 10MB.
Aside from Maps (for which there were alternatives) the other apps haven't really had any urgent patches bundled into minor OS upgrades that I can recall.
One could even say that the advantage of Google being able to system app updates on the Play Store is that Android apps competing with iOS ones (not a great comparison, but Google Now and Siri) have an advantage in that Google keeps on pushing updates regularly as and when they are ready, whereas Apple would update Siri during a major OS update or the incremental ones. [I am aware that back-end services/responses are updated regularly by both, but I'm referring to code which would change an app's behaviour].
This is not true for apps that come with the OS. Some Apple apps were updated later, but only those that come from the App Store like any other regular 3rd party app.
The advantage Google has to be able to update core apps from the store instead of through OS updates is specific to Android's nature, because it allows them to work around OS updates not being available to customers (because of carriers, OEMs, whatever). Apple doesn't have that problem because they update the OS themselves. Also, Google likes to update its software more often than Apple does.
Yes they do: http://cdn.macrumors.com/article-new/2013/09/ios_7_0_2.jpg (since iOS 5).