Apple's iPhone 4 introduced several significant hardware upgrades over previous models, specifically a much improved screen and a camera capable of HD video recording, LED flash, a second, forward-facing camera and a built-in gyroscope.

It was going to take developers a little while to start releasing apps that took advantage of these improvements, but now they're here let's look at the 10 best apps to showcase the iPhone 4's new functionality.

1. Zen Bound 2 - £1.79

(iPhone 4 hardware feature: Gyroscope)

Zen Bound 2 is one of the most unusual, but strangely satisfying, iPhone games you'll ever play. Essentially you have to wrap a rope around different 3D objects by rotating them as they float in space. Zen Bound 2 makes use of the iPhone 4's built-in gyro to add another level of control to your rotations.

Zen bound 2

2. Fring - free

(iPhone 4 hardware feature: Front facing camera)

We know the iPhone 4 has FaceTime for video chat, but it only works over Wi-Fi networks. If you want to break free of this restriction then install Fring and use that to video chat to your friends over 3G. It even works with phones running the Android operating system, not just other iPhone 4 users.

Fring

3. The Elements for iPhone 4 (UK version) - £5.99

(iPhone 4 hardware feature: Retina display)

The Elements for iPhone 4 is a special edition of the Theodore Gray's enticing guide to the periodic table of the elements, which has been specially created for the iPhone 4 to make use of the fabulous retina display. The beautiful high resolution graphics make science come to life in your hands.

The elements for iphone 4

4. TuneIn Radio - £1.19

(iPhone 4 software feature: Multitasking)

Before iOS 4 introduced Apple's take on multitasking, apps like TuneIn Radio, which enables you to listen to and record Internet radio (yes, including BBC 1, 2, 3 and 4) had a hard time getting by. But thanks to iOS 4 you can now listen to the radio in the background while doing other tasks, like email, web browsing or running other apps, which is exactly the way it should work.

TuneIn radio

5. You Gotta See This! - £1.19

(iPhone 4 hardware feature: Gyroscope)

You Gotta See This! makes innovative use of the iPhone 4's gyroscope. You simply start a recording, swipe the scene up, down and left and right with the iPhone 4's camera and it uses the gyroscope to determine the camera orientation, producing one large image, with the individual images you took positioned correctly. Check out #seethis on Twitter for examples.

You gotta see this

6. N.O.V.A. - Near Orbit Vanguard Alliance - £2.99

(iPhone 4 hardware feature: Gyroscope)

Before the iPhone 4, N.O.V.A. was a damn good first person shooter. After the iPhone 4 it became an even better one because it uses the iPhone 4's gyroscope as a controller aid. The game itself is a sci-fi adventure reminiscent of the Xbox's Halo, but all you really need to know is that if it moves, you generally shoot it, and that's not a bad thing.

NOVA

7. Rubik's Cube - £1.79

(iPhone 4 hardware feature: Gyroscope)

This is the only 'cube' app approved by Mr Rubik himself (his first name is Erno, in case you were wondering), so that's a real seal of approval, if ever we saw one. iPhone 4 owners can get a little extra from the app thanks to the new gyroscope controls. Now you can flick your wrist to make a move, and of course there are improved graphics for the iPhone 4's retina display.

Rubiks cube

8. Eliminate: GunRange Free - free

(iPhone 4 hardware feature: Gyroscope)

If you want a quick and dirty way to understand what the iPhone 4's gyroscope is all about then check out Eliminate: GunRange Free It's quick and dirty, but in a good way. In fact, we had this one demonstrated to us by staff in our local Apple Store, when showing off what the iPhone 4 can do. You aim your gun by moving the iPhone 4, and tap to fire. There's also a 59p paid-for version if you need more to shoot at than the free version offers.

Eliminate gun range

9. iMovie - £2.99

(iPhone 4 hardware feature: HD video recording)

Now you've got a HD capable video recorder in your pocket you might as well make use of it. Apple's iMovie app enables you to turn your videos into mini masterpieces right on the iPhone 4 then upload them to YouTube. It's understandably limited compared to the full OS X version of iMovie, but it's still an essential app for the iPhone 4.

iMovie

10. Torch for iPhone 4 - 59p

(New iPhone 4 hardware feature: LED flash)

Here's an app that does what it says on the tin: Torch for iPhone 4 It turns your iPhone 4 into a torch by utilising the LED flash. It's a simple idea, and works surprisingly well. You can even use it to send morse code messages, should you ever feel the need.

Torch for iphone 4

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Liked this? Then check out Top 20 best free iPhone apps

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