iOS7.1, the first major update to the company's mobile operating system since its launch in September, brings a host of new features and tweaks.

There may not yet be a single production car currently on sale that offers support for CarPlay, Apple's new technology for mirroring an iPhone's screen and its apps on the dashboard, but that hasn't stopped Apple from enabling the feature on iPhones in anticipation via iOS7.1.

But as well as prepping its customers' phones for the future, the new update, available to download now for iPhone 4, 4S, 5, 5C and 5S, brings new graphical icons for features such as FaceTime, the voice call dialer, and messaging.

Users will also get more control over how Siri, Apple's voice activated virtual assistant, works. Rather than cutting off automatically after a set time, Siri will stay active and attentive as long as you're holding down the homekey.

The camera function is also improved and for owners of the iPhone 4, which has struggled under the weight of the new operating system, Apple promises the new update will be a noticeable improvement in terms of smoothness and speed.

As well as new features, the update fixes a number of bugs, including the homescreen crash that some users had complained about and an improvement to how the Touch ID fingerprint sensor on the iPhone 5S performs.

To install the update, simply go to the iPhone Settings menu, select General and tap Software Update. However, be sure to back up first, whether via iCloud or a tethered PC or Mac.