Lots of Apple's competitors offer software-based battery-saving modes for their devices, and Apple will do the same when it launches iOS 9. It's a wonder that it's taken this long, but Apple says "we know you all turn things off to try and make your devices last longer. The new low-power mode will switch levers you didn't even know existed". It should give up to three hours of extra use, on top of the extra hour or so you'll get simply from updating to iOS 9, which is more power efficient than iOS 8.

iOS 9 feature rumour: Multiple user accounts

One of the most wished-for features in iOS 9 is the ability to have multiple user accounts, combined with proper parental controls.

At the moment, there are parental controls present in iOS 8 that let you set restrictions about the content that can be consumed on the device, but you'll need to turn them on and off constantly if you want to use the iPad or iPhone once your child has finished using it.

The introduction of the Family Sharing feature in iOS 8 suggests that Apple might be open to the idea of multiple user accounts in the future, but there was no mention of it during the iOS keynote.

iOS 9 feature rumour: Control Centre customisation

We love the Control Centre, which was introduced with iOS 7 to give users quick access to toggles for Bluetooth, WiFi and more, as well as other settings. We'd like Apple to take this a step further, allowing us to customise the Control Centre to give access to settings that we find ourselves needing regularly.

Unfortunately, as with multiple user accounts, there was no word of it during the keynote.

There are even more iOS 9 features that we were keeping our fingers crossed for. You can read about them in our 9 things we want to see in iOS 9 article.

iOS 9 features: Impossible to jailbreak

Other reports said that Apple has found a way to prevent people from jailbreaking their iOS devices, with a new system called 'Rootless'. It's a feature that many users won't be pleased to see, and it's unlikely that Apple will talk about it during WWDC. See also: How to downgrade from iOS 9 to iOS 8.