iOS 13: New iPhone and iPad software available now – but Apple warns users not to install it

Downloading update means 'living on the edge', Apple cautions

Apple has released its new iPhone operating system to developers – but advised them not to do so.

The company has held its Worldwide Developers Conference, during which it showed off iOS 13, the software that will power the iPhone. It comes with a range of new features, including a dark mode that turns the entire operating system black.

Apple said the new update will arrive for the public in the autumn. Users can sign up to the public beta to get it early, receiving work-in-progress versions of the software in July.

But developers were given access to it as soon as the keynote was finished, allowing them to download it from Apple's website and launch it on their phones.

That option came with a specific warning, however, cautioning users that downloading the new update could cause damage to any phone it is added to.

"Important Note for Thrill Seekers: If you're interested in living on the edge and trying out the great new features in iOS 13, we strongly advise waiting for the many bug fixes and refinements coming to the public beta later this month."

The warning is a marked departure from last year's iOS release, which in its very first version was faster than the mature operating system it replaced. That time around, Apple had focused on performance and efficiency, and it was clear in the very first builds that were released to developers.

Last year, Apple also allowed developers to download the update as an "over-the-air" release, letting the phone download and update itself. It also made it relatively easy for anyone – even people who weren't registered developers – to download it, since any phone could be given the ability to do so.

With iOS 13, Apple is not offering that option at all. Instead, it is requiring users to plug into iTunes – the app it killed during the same event – and use that software to download the update and then push it onto the phone through a wire.

That option is available to anyone who is a registered Apple developer, which costs $99. Apple will check that anyone attempting to download it has one of those accounts, and won't allow phones that belong to anyone else to get hold of it.