Apple has released new iOS version today, iOS 8.1.2 with some bug fixes and addressing an issue i s purchased through iTunes Store. If you are faced to this issue solve the problem by visiting itunes.com/restone-tones . Now you can download iOS 8.1.2. and update through the OTA or using iTunes. To iOS 8.1.2 has released as build number 12B440 for iPhones ,iPads, iPod touch
If you are wiling to jailbreak iOS 8.1.2 there is no proper update yet. The latest iOS firmware supported with iPhone 4s , 5, 5c, 5s ,6, 6plus , iPad mini, 2, iPod touch 5th gen, iPad Air, Air 2, iPad mini retina display. If you are hope to update to iOS 8.1.2 through OTA follow the settings > general > software update > download and then install.