Apple released iOS 7 beta 4 today to developers, hopefully bringing some new features and bug fixes to the next version of Apple's mobile OS. Apple was on a two week release schedule with beta 2 and beta 3, but this fourth version is arriving at the three-week mark. This version is arriving a few days after the developer portal was reopened following a malicious hack on the site.
The latest version is available over-the-air via Settings > General > Software Update on devices running the current iOS 7 beta. Developers can also download it manually from Apple's developer website.