twitteroauth is the first PHP Library to support OAuth for Twitter’s REST API. It is developed by Abraham Williams. You can download the source code @ GitHub and the example inside is quite easy to follow.
GitHub – abraham / twitteroauth
 

Unlike the Facebook API, the Twitter API does not support logout. If you want to increase the security, you can force user login every time when he/she clicks the Signin with Twitter button. This can be down by adding the force_login parameter in the GET oauth/authenticate request.
Twitter API – GET oauth/authenticate Continue reading twitteroauth – Force User Login →