Apple today released the fourth beta of iOS 7.1 to registered developers for testing purposes, following the release of the third iOS 7.1 beta at the beginning of this month. The update has a build number of 11D5134c and is available via an over-the-air update or through Apple's developer center website.
Today's update also includes Xcode 5.1 Developer Preview 4 and a new version of the Apple TV beta software. Earlier today, it was rumored that Apple would soon be releasing the next beta of iOS 7.1.
Article Link: Apple Releases iOS 7.1 Beta 4 to Developers