Use Twitter API In Android App For Send Tweet only.
First you have to register your Twitter Developer Account.
On below Link.
Then Create one Application on your developer Account.
Give proper Name for your twitter application.
Now It should be generate your twitter Consumer Key And Consumer secret
Then This Two Key you should be Paste on Below Code.
Now Change your Application Type.
Read, Write and Access Direct messages
Check this Screenshot.
Download And Enjoy Code.