I wounder if the source code for Twitter android app is released??
It's been anounced to be open sourced in the future, but it still isnt.
See this tweet from a Google developer: http://twitter.com/#!/vdobjanschi/status/8775784206438400
Twitter is now responsible to open source the app. Please direct your question to the Twitter Mobile team.
Not that I'm aware of - I've been searching as well and can find a number of "official" references to it being open sourced soon (namely: a post by Tim Bray in may - http://android-developers.blogspot.com/2010/05/twitter-for-android-closer-look-at.html)
Twitter 4 j ... is the answer. The SDk to integrate twitter to an Android app. You could find the tutorial here
It provides various features as tweeting through code, make a tweet favorite, destroy favorite for a tweet... And Of Course the authorizations