Apple has seeded iOS 7 Beta 2 for Developers few minutes ago. You can download iOS 7 beta 2 via OTA update if you have already installed iOS 7 beta 1 on your iPhone 5 or iPod Touch. Otherwise download the latest release from developer portal. This update brings so many bug fixes and system improvements overall.
Change log of Apple iOS 7 beta 2 yet to be updated on apple website.