Opauth is an open source PHP application for login with google, twitter or facebook authentication app that removes the inconsistencies between providers and offers a standardized method for dealing with them.
Opauth as a framework provides a set of API that allows developers to create strategies that work in a predictable manner across PHP frameworks and applications.
Currently, 3 providers are almost plug ‘n’ play: Google, Twitter + Facebook and there are more to come. Also, there is support for dealing with any other Oauth provider.
Also, it integrates well with PHP frameworks including CakePHP, Yii and others to be added soon.