Have you been testing iOS 9 betas and iOS 9 GM [Golden Master version] on your iPhone, iPad or iPod touch? Apple launched the first Public Beta testing program this year and a lot of users were searching for bugs in the new firmware this summer. How it is possible to update to iOS 9 from beta or GM version?
As soon as Apple released iOS 9 firmware to public users started to ask the same question: if iOS 9 GM update to final version is possible or not. It is possible and you can also find out what to do and how to get iOS 9 OTA update if you were testing beta firmware releases and / or the last GM build 13A340 that was unveiled earlier in September.
GM or Gold Master version always precedes the public firmware launch. Still iOS 9 public version has a different build number than the GM and thus users wish to upgrade to the final platform offered by Apple. Since its build number is different [it is 13A5344] you should get the OTA update option and download the latest version available.
Since there are a lot of users with iPad, iPhone and iPod touch who are trying to use iOS 9 OTA update feature – the high traffic might cause errors and not let you install this platform right away. If this is the case you should manually update via iTunes by downloading the ipsw file through direct iOS 9 download links or download it directly from iTunes [if high traffic doesn’t lead to issues].
Remember that Apple is taking iPhone 6s pre-orders and also testing iOS 9.1 beta now so you might want to get this firmware version instead of public iOS 9 if you are planning to continue testing and reporting bugs you find this fall.
Users who have a jailbroken iDevice will not get the OTA update for iOS 9 as they will only see ‘Checking for Update’ message in General menu. If you want to lose the jailbreak and get this firmware you should use iTunes for upgrading.