Apple releases iOS 9 GM to developers ahead of Sept. 16 release
Following a huge special event on Wednesday, Apple released the golden master build of iOS 9 for developer testing ahead of an announced public launch date on Sept. 16.

A golden master release means Apple is testing final revisions of its upcoming iOS 9 update before an expected launch next week. Two days after iOS 9 is expected to drop, Apple plans to open sales for next-generation iPhone 6s and iPhone 6s Plus hardware, which will ship with the new operating system.
Apple is introducing a number of new features with iOS 9, including a greatly enhanced Siri virtual assistant that proactively searches surface search results, make decisions based on contextual clues, conduct deep searches and more. Smarter backend algorithms will power mock artificial intelligence capabilities to support more natural user interactions.
Along with Siri, iOS 9 brings improvements to Maps with an all new Transit feature, while other built-in apps like email and notes feature UI overhauls. A few apps, like News and Wallet, have been renamed to reflect substantial modifications to their content and operation.
As of this writing developers are receiving the iOS 9 GM in an over-the-air update.

A golden master release means Apple is testing final revisions of its upcoming iOS 9 update before an expected launch next week. Two days after iOS 9 is expected to drop, Apple plans to open sales for next-generation iPhone 6s and iPhone 6s Plus hardware, which will ship with the new operating system.
Apple is introducing a number of new features with iOS 9, including a greatly enhanced Siri virtual assistant that proactively searches surface search results, make decisions based on contextual clues, conduct deep searches and more. Smarter backend algorithms will power mock artificial intelligence capabilities to support more natural user interactions.
Along with Siri, iOS 9 brings improvements to Maps with an all new Transit feature, while other built-in apps like email and notes feature UI overhauls. A few apps, like News and Wallet, have been renamed to reflect substantial modifications to their content and operation.
As of this writing developers are receiving the iOS 9 GM in an over-the-air update.
Comments
Public Beta schlubs appear to be out of luck as far as getting the GM.
Time will tell, public beta folks may just be delayed and true Devs get priority, which actually makes sense...
IMZDL Word.
I'm surprised the developer GM is OTA. In the past it's always been a download. In any case based on past experience I wouldn't trust a BETA to GM (in most cases a final release) via OTA. A fresh install with a backup restore gives better piece of mind. Too many things can go wrong with an OTA upgrade. Ever have an iPhone problem and go to the genius bar? First thing they do is a fresh install. Public BETA users, hold on, it's coming soon.
Ugh, having some major boot loop bugs and cannot restore from backup after going from the latest iOS 9 public beta to iOS 9 GM (iPhone 5s) -- cannot get rid of the slide to restore loop. Exasperating Apple! DFU restore does not fix, the problem is at the restore...
Registered dev here, no update yet. Switzerland. (Update: N/A over the air. Downloadable through devcenter.)
Seems to be the same here in the U.S. If I recall correctly (albeit vaguely), I'd get the GM as OTA if I wait for the public release next Wednesday. I think I prefer the "wipe and load full install from GM download" method, in case all the delta updates somehow missed a file here and there. But if I'm going to go that route, I may as well install the 9.1 beta instead of the 9.0 GM. I presume the 9.1 beta is built off the 9.0 GM.
On our test iPad Mini2/128GB, the only way got it to finish restoring was to continually unplug and replug the Lightning cable, and then the next sync would find 10 more apps to sync, and then stall, unplug/replug, 10 more apps, stall, unplug/replug, etc.
No better luck on a 64GB iPhone 5S.
A complete, unimtigated disaster.