Search Tweets using User Oauth in android with the help of Twitter API


I have searched lot but i couldn’t find any sample code that explains how to search tweets using user based oauth.There are numerous links that explains how to use App oauth to fetch tweets(450/app) but i dint come across a single link that shows me how to implement OAth Signed authentication to fetch tweets(180/user).Does OAth signed authentication means redirecting the user to Browser and authenticating user then using the access token (from the callback)to fetch tweets? However i read that the access token has to be authorized before searching tweets so how do i authorize this access token to fetch tweets? There is so much of confusion …Please provide some code sample for implementation of OAth signed authentication for searching Tweets in android