Apple released today, both to developers and members of the Apple Beta Software Program, the fifth beta version of iOS 9.1 (compilations 13B137 and 13B139, this for iPhones 6s / 6s Plus). She arrives less than a week after the fourth.
As always, Apple indicates that it only brings "bug fixes and enhancements". The only visible changes in iOS 9.1 are new Emojis (shown above) and some new wallpapers.
IOS 9.1 is the operating system that will be installed on the iPad Pro. As it will soon start to leave the production lines to be delivered in early November, the GM version (Golden Master) should be released soon. IOS 9.1 will also be required for the configuration of the new Apple TV.