If you’d like to test drive Apple’s next iOS version, simply sign up for their public beta program here, enroll your device, and, after a quick reboot, you should see in the “Updates” tab in Settings the public beta of iOS 9.1 available for download.
Yesterday, Apple released the first developer beta build of iOS 9.1, one of the next updates to Apple’s soon-to-ship iOS 9 operation system for iPhone, iPad, and iPod touch. Today, Apple seeded public beta testers with the first public beta build of iOS 9.1. Not too much has changed in this build according to users, but most are reporting that they’re seeing much improved performance and speed when compared to the Golden Master build of iOS 9. There are new APIs for developers building iPhone 6s apps with 3D Touch and Live Photos, but little else seems to have changed.