Does Twitter has the iPhone SDK which has a login popup like facebook iOS SDK?
It doesn't have. What I can recommend you is to use this DDSocialDialog library (just 4 classes) and you can have something similar
No Twitter does not have the login pop up as facebook has
. You have to create your own login page. or you can get few from the open source.
Matt Gemmell and Craig Hockenberry, developer of Twitterific created MGTwitterEngine, an easy-to-use library of classes providing methods that make it extremely easy for the developer to access the Twitter API. see I believe there are a few other libs out there, but it's just as easy to roll your own because like Macha says above Twitter's API gives you the option to have the feeds in XML or JSON format.
Try this link MGTwitterEngine
hAPPY cODING...
Look for this source code:
http://github.com/bengottlieb/Twitter-OAuth-iPhone
Thanks to Ben Gottlieb.
It opens the login page as a modal view.