Apple has released the fourth developer beta of iOS 9.
Featuring a build number of 13A4305g, the fourth iOS 9 beta lacks specific release notes, but likely continues to focus on improving the stability and reliability of the new features in the operating system.
A new watchOS beta with a build number of 13S5305d has also been posted, which can be installed via a configuration profile that requires the corresponding iOS 9 beta to be installed, along with new betas of Xcode 7 and Apple Configurator.