A lot has happened since Android 4.0, Ice Cream Sandwich.
Half of the smart phones out there use Gingerbread, Android 2.3-2.37. It works but it is clumsy.
With 4.1, Jelly Bean , we got a much smoother and more responsive interface and a much more flexible system of placing icons on the home screen.
With 4.11 and 4.2, maps got a lot better and would allow you to download local maps, so you can navigate even if you don’t have reception (as long as you calculate your route while you have reception).
Google Now got a lot better from 4.1 – on. It answers complicated spoken questions. It knows my work routine and tells me the expected traffic delays and calculated ETA when I go to work and come home. It notices when I leave the home or office wi-fi signal and generates a traffic message.
4.2 has “folders” on your home screens so you can put all your social apps in one and messaging apps in another and tools (wi-fi analyzer, calculator, speed test) in another.
4.3, just released, has a smoother, “more buttery”, response to touch. It has an improved bluetooth and an “always-on” wi-fi can be selected to know where you are at all times (you can turn this off, of course). It has better battery life and the ability to limit what apps children can download. It will be the last Jelly Bean. Key Lime Pie will come out at year end.
In a word the industry has really had some shakeups. Many of the early Gingerbread phones can’t be updated to Jelly Bean due to technical issues (like not enough RAM)and they are still on an old 2-year upgrade cycle. They can’t keep up with the little updates because they want to keep a fancy “shell” on top of plain Android and it takes time to re-write the shell. For this reason the pure Android phones, the Nexus phones, get the upgrades first, for me, I waited less than a week.