How to download and install iOS 10 on your eligible iPhone or iPad when the time comes
Here's when the update will likely hit some of the major time zones around the world:
Additionally, we need to make sure that you own an eligible iOS device. Here's a list of all the devices that will be getting the update:
Warning: Make sure to backup your device before you update your iPhone to iOS 10. One can never know, and a handy iCloud or iTunes backup will save you lots of trouble. The easiest way to manually enforce a backup is by going to Settings > iCloud > Storage & Backup and tapping the large Back Up Now button at the bottom of the display.
So, how to get the update? There are two ways, one easy and the other one beng a tad more complicated:
1. Wait for the OTA update
Naturally, you'd want to click on the Details button in order to go to the Software update menu, which can be found in Settings > General. There you will see general information about the update. At the bottom, you should see a Download and install button, just tap on it and follow the on-screen instructions, and you will be running iOS 10 in no time.
We've heard some old wives' tales that continuously opening and closing the Software update menu will let Apple know you are desperate to receive the update now, but the scientific community is yet to prove these unfounded claims.
2. Install iOS 10 manually via iTunes
Users who are more comfortable the iTunes way can hook up their gear to the computer, find their device, and click the "Check for update" button, though you should receive a prompt for an upgrade on the fly. Just click the Download & Update button (pictured right below), and you will have your iPhone, iPad or iPod touch brought up to iOS 9 in no time.
Finally, we'd advise you somewhat counterintuitively to wait a little bit with the iOS 10 update. There have been occurrences when Apple's activation servers go down on account of the monster amount of immediate requests, and if you hit that button at the second the prompts appear, you might be left with a device that has no restoring in sight until the servers get up again.
Thus it'd be wise not to jump the gun immediately, but do it in the evening at home or the next morning depending on your country of origin, when the initial rush has watered down.