When I updated my iPhone to iOS 9, I was forced to choose a six-digit passcode instead of a four-digit one, and it's getting on my nerves. Is there a way to go back to a four-digit passcode?
Yes, you can change the six-digit passcode on your iPhone (or iPad) back to a four-digit passcode in iOS 9, and it's actually really easy - it's just that the option to do it isn't particularly well signposted. In this brief tutorial we'll show you how to switch back to a four-digit passcode without losing the rest of iOS 9's features.
How to change passcode from six to four digits in iOS 9: Settings
The option you're looking for is in the Settings app. Select the Touch ID & Passcode tab from the menu on the left (you'll have to enter your current - presumably six-digit - passcode to access this section), then tap Change Passcode (in blue text in the third section down). You'll have to enter your old passcode yet again.
But now, when iOS 9 asks for your new passcode, tap Passcode Options. (It's easy to miss.)
From the menu that pops up, select 4-Digit Numeric Code, and the number of blanks in your new passcode will drop from six to four.
Enter a four-digit passcode, verify it, and you're there: you're back to the happy days of four-digit passcodes.
How to change passcode from six to four digits in iOS 9: Why does my iPhone's passcode have six digits now?
As part of its drive to increase security on Apple devices, the company now (in iOS 9) by default requests a six- instead of a four-digit passcode when setting up a new (or newly updated) iPad or iPhone. This is more secure, of course, but slightly annoying, and some of the strategies we've heard people using to stretch their four-digit passcodes into six digits without having to memorise a new number suggest that security is not going to benefit a huge amount.
How to stop your four-digit passcode changing into a six-digit passcode
If you haven't yet updated to iOS 9, bear in mind that you should be able to get round this problem by simply making sure you've got a (four-digit) passcode switched on before starting the install. When the update completes, you should still have the same passcode, with the same number of digits. The problem only appears to occur if you turned off your passcode before updating.
I made the mistake of turning off the passcode on my iPad Air 2 for an unrelated reason, then going through the iOS 9 install process. I only realised the error when iOS 9 asked me to create a six-digit passcode at the end of the update. Don't make my mistake - but if you do, well, as you can see above it's not the end of the world.