Apple has rolled out iOS 9.1 for supported iPhone, iPad and iPod touch devices with new features, bug fixes and improvements including new emojis.
If you are on a jailbreak with iOS 9.0.2 then you are strictly warned to stay away from this new update as Apple has fixed the jailbreak exploits with this latest iOS 9.1 and the Pangu jailbreak which worked on iOS 9.0.2 is no longer capable to jailbreak iOS 9.1. So if you want to have a jailbreak then you will need to wait and stay with the iOS 9.0.2.
While you can always update to latest iOS version Over-The-Air (OTA) by going as
Settings > General > Software Update
You can also download the iOS IPSW on your PC/Mac and update/restore to the latest software update via iTunes.
iOS 9.1 download IPSW links