iOS 8 will be available as an over-the-air (OTA) update for the iPhone 4s and later, iPad 2 and later, iPad mini, and the fifth-generation iPod Touch starting at around 10:00 a.m. PT (1:00 p.m. ET) on Wednesday, September 17, 2014, but that doesn't mean you'll see it in your Software Update panel right way.
Apple releases major, whole-number iOS updates as "rolling" releases (sometimes referred to as pulsing) to ease the congestion on its network and to ensure that most users will have a positive experience downloading and installing its latest release. It's like those traffic lights at some onramps that artificially slow the flow of cars onto the freeway during rush hour.
Rolling releases are common sense. If Apple pushed iOS 8 onto everyone's device at exactly 12:01 am PT, it's servers would melt down and cause a lot of grumbling on blogs and in the media. Besides, not everyone wants to download iOS 8 today – and hey, it's not the new U2 album – so why melt the global fiber optic lines and tax Apple's brand-spankin-new Content Delivery Network (CDN) unnecessarily? It's not good business.
If you want to get iOS 8 first, here are a some tips.
Backup all your target iOS devices right now. Don't wait for iOS 8 to land only to remember that you didn't make a backup. Do it now, so that you're ready to go as soon as iOS 8 hits your Settings app. This document explains how to backup your iPhone or iPad to iCloud (usually my preference) but iCloud is going to start slowing down under the traffic soon, so you might want to backup via USB to iTunes for greater speed.
Clear out the cruft. If your an app hoarder or have a lower capacity iOS device, take a trip to Settings > General > Usage and ensure that you have at least 2.5GB of available storage. iOS 8 is a large download and it won't install if you don't have enough free space.
If you're a registered developer (and impatient), you can download the "iOS 8 GM Seed" (short for "Golden Master") version of the code right now. It's labeled "build 12A365" and was posted to Apple's Developer Center on September 9. While the final release can sometime vary from the GM, this doesn't happen often. Beware: the full restore .ipsw file is a weighty 2.0GB (iPhone 5s) and 2.2GB (iPad mini) so prepare to wait even on a fast connection.
One of its dirty little secrets is that Apple doesn't push software updates automatically to your Settings app. Sometimes you'll see the red software-update-is-waiting badge on your Settings app, but most times you won't. In order to get the iOS 8 update as soon as possible, you need to manually touch Settings > General > Software Update and force it to check.
Lastly, if you're tired and need to get some sleep before the big day, make sure that your iPhone or iPad is connected to Wi-Fi and power before you go to bed and it will continue to check for the iOS 8 update overnight. If you're lucky, it'll be waiting for you when you wake up in the morning. (If you don't see the push notification or Settings badge in the morning, touch Settings > General > Software Update to force another update.)
Pro Tip: Update all of your iOS apps now (easily done with "Update All") ahead of the iOS 8 release. There's a crush of updates coming out day-and-date with iOS 8 and Apple's CDN may buckle under the load of the increased traffic (remember the horrible video stream from Apple's live event?).
Enjoy it and post the arrival time of iOS 8 (and your locale) in the TalkBack below.