airlineuser
(a code review tool used by Android.)
I think most app devs look at the installed base numbers and choose to support 2.1+ or 2.2+. I can't think of any APIs in 2.3 or 3.0 (or even 4.0) that are so wonderful that they are worth cutting off such a large part of the potential customer base.
Example: The latest hot Android game is "Wind-up Knight". It supports Android 2.2 and up.
https://market.android.com/details?id=com.robotinvader.knigh...
As to why you see younger attendants on short flights, that's because long flights are more desirable for senior flight attendants. The way the flight bidding system works, a senior fa can fulfill their monthly flying hours quota by working 8 days of trans-Pacific flights at the start or end of a month, leaving the rest of the month free.