Apple has started to roll out iOS 15.4.

The latest iPhone software update, which has been available as a public beta since January, is available to download onto compatible iPhones now. It will also be preinstalled on the iPhone SE (2022) when that arrives on Friday 18 March 2022.

The new software version brings with it a few interesting changes to how compatible iPhone models work. 

The headline addition involves Face ID, with a tweak allowing for the facial recognition software to work even when a user is wearing a mask. This follows on, of course, from a previous workaround Apple created, in which Face ID's usual security checks could be bypassed if a user was wearing an Apple Watch linked to their iPhone.

For those that don't own one of Apple's smartwatches, though, this should prove to be a helpful little feature.

It's not the only thing notable from the update, though. 

Apple's new Tap to Pay feature is also part of it, which allows compatible iPhone devices to be transformed into terminals for contactless payments. While not a mass-appeal feature, it does mean that the iPhone now has the potential to become a digital register and, for those with businesses that rely on dedicated card readers, allows them to do it all from a smartphone. 

There's a new safety feature landing for AirTags too, which sees iOS devices warn users against using the item-tracking pucks to track a user's location without consent. 

In terms of compatibility, iOS 15.4 is available to any device that already supports iOS 15. That means anything from a first-gen iPhone 6S to one of the iPhone 13 models should support it.