2.3 still runs on 16% of android phones:
https://developer.android.com/about/dashboards/index.html
3 karma · joined September 10, 2012
Native apps are much nicer and easier to code, regardless of the platform. And don't even get me started on the mess that is trying to use JS frameworks such as Jquery mobile to actually do something useful. Such as facebook or twitter integration.
Cross platform app development is a good ideal but none of the current platforms can do it in a way that isn't a horrendous pain.