Best version of android to develop for?

[hppd]

Hello,

I want to get into making android apps, but before I begin I was wondering what is the best version of android to develop for? Should I use 2.2.3 or something (Because a lot of people still use that). Or should I take another version?

EDIT: I found this http://developer.android.com/about/dashboards/index.html

Seems like it would be legit to start developping for 2.2.3 so everybody can use the apps..

[r00k]

Ubuntu touch!

http://www.ubuntu.com/phone

I don't know much about developing, but being Ubuntu i can't imagine it being too difficult. As well as being a fairly unpopular OS it needs help.
Edit:
Apologies for being a bit off topic, by android i thought you meant mobile OS thats not apple  . But if you'd like to look into it i think you might find it beneficial.