As expected from many rumours, Apple has released the iOS 7.1 update for iPhone and iPad. There have been several bug-fixing updates since iOS 7, reviewed, was released in 2013, but 7.1 adds a few significant new features along with a load of interface tweaks.

iOS 7.1 new features: CarPlay

Chief among the new features is CarPlay, which we've covered in depth already. Previously called iOS in the Car, it will allow you to more easily use your iPhone (or iPad) while driving. You'll be able to access maps, directions, messages and music on a bigger screen in the car and be able to use Siri by pressing a button on the steering wheel.

The catch is that only certain brand new cars will support CarPlay in 2014, so it's a non-feature for most people. We're hoping manufacturers such as Pioneer, Alpine and others will launch aftermarket in-car entertainment systems which support CarPlay. That way you'll be able to use it in older cars. Not everyone is happy to welcome Apple into their car though - I fear the Apple-controlled car.

iOS 7.1 new features: Siri

There's big Siri news for UK iPhone and iPad owners. At last there's a choice of voices: male and female. Plus, the old male Siri has been given the boot, and there's a new, friendlier-sounding voice. Gone is the shouty, angry-sounding Siri: a posher Siri has taken over.

With the update, you can now hold the Home button down while talking to Siri. Only when you release it will Siri stop listening and respond. It's a small change, since you could previously tap Done to tell Siri to stop listening, but it's a more natural way of doing things, as if you were using a walkie talkie.

iOS 7.1 new features: Interface

Version 7 was a major interface update for iOS, but it wasn't popular with a lot of users, particularly those with eyesight problems. The main complaint was a lack of contrast, with light-coloured text on bright white backgrounds proving hard to read.

The bad news is that Apple hasn't done much to alleviate the problem. The phone dialler screen now has a small green circle for beginning a call instead of a large rectangle. There are also similar green and red circles for answering or declining incoming calls instead of larger rectangles:

If your iPhone is locked, there's still no decline option when someone calls - just a redesigned 'slide to answer' bar:

However, the keyboard now has highlighted Shift and Backspace keys, which are easier to see, and in the Music app, the Shuffle and Repeat buttons are also highlighted.

A complaint which has been addressed is the difficulty in turning off wallpaper motion. In iOS 7.1, there's a prominent option to toggle motion on and off when you're choosing a wallpaper, instead of having the setting buried deep in the accessibility options.

Other minor tweaks including cancelling FaceTime call notifications when you answer on a difference iOS device, and there's a new split-screen 'Month' view in the Calendar app which shows appointments for the selected day in the bottom half of the screen.

iOS 7.1 bug fixes

Many iOS 7 users have reported random crashes, and we've experienced plenty of them, both on iPad and iPhones. You'll be running an app and all of a sudden the screen turns white and the Apple logo is displayed. A few seconds later, you're back at the lock screen. We'll have to see if this is fixed by the update - it's too early too tell.

Another bug we've encountered is where the lock screen on the iPhone is corrupted and displays landscape instead of portrait, but it's impossible to use the slider to unlock the phone. Only turning it off and on again fixed the issue. Again, it's too early to say if this is definitely fixed, but Apple claims it's ticked off the list.

iOS 7.1 new features: iPhone 5S

If you have an iPhone 5S, there are a few tweaks just for you. In the camera app, the HDR mode will automatically turn on if the scene demands it - a feature we've seen before on Android phones.

There are also improvements to the burst shooting mode, and Touch ID - to make it faster and more accurate.

iOS 7.1 new features: iPhone 4

We've not had a chance to test this out yet (we will report back shortly), but Apple says performance is much improved for iPhone 4 owners running iOS 7. For many people, the sluggish performance - even when using basic functions such as the phone dialler - meant they yearned to go back to iOS 6.

Better performance was promised with iOS 7.1, so we'll run some tests and see whether the update has made the iPhone 4 usable again.

How to get the iOS 7.1 update

Whenever Apple releases a big iOS update, millions of users try to install it at the same time. We've had a mixed experience with 7.1, with some people downloading and installing it fine, and others having the common "Software Update Unavailable" error message. You may also need to install pending updates such as iOS 7.0.6 before you'll see the iOS 7.1 update notification.

If your iPhone or iPad doesn't notify you of the update, simply launch the Settings app, tap General and then Software Update. Be sure to backup your device before performing the update, and you'll need enough free storage and sufficient battery power as well.

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