The Apple iPhone comes with a whole load of applications already built into it - some you'd expect, like email and a calendar, while others are innovative, such as the digital compass and the ability to reorient the GPS-powered maps to match the direction you're facing.

It goes without saying that another built-in iPhone application is the 3-megapixel camera, which also allows you to shoot video, the voice recorder for memos, etc. and, of course, a web browser (Safari) for surfing the Internet.

With the new iPhone 3GS, you have access to a comprehensive stocks application, you can watch YouTube videos, it has full voice control, and a virtual keyboard.

One of the more unusual apps is the way it support the Nike + iPod Sensor (which unfortunately is an extra) - you just slip the sensor into your shoe, start your workout, and the Nike application on your iPhone gives you all the info you need to make sure your exercise session is just what you need.

But what makes this phone so appealing is the massive number of third party iPhone 3G applications that are now available, with more being released all the time.

One of the most popular categories is, not surprisingly, iPhone games, with classics such as Tetris being available, as well as plenty of others to suit every possible taste. These include flight simulators, sports such as tennis, and poker, to name but a few.

You'll also find plenty of social networking apps to interface with Twitter and Facebook, for example.

But there are plenty of more serious iPhone applications available.

There are applications to help manage your day-to-day life, such as shopping lists, gas mileage trackers, expense trackers, inventory management.

Reference information and reading material are in no short supply either, from the works of Shakespeare, to recipes, and of course you'll never be without the news or weather, and because your iPhone is GPS-enabled, you can easily receive weather reports based on your current location.

In fact, no matter what you're looking for, you'll probably find an iPhone 3G app that is exactly what you want.

Now, once you've been through the iPhone application download process, there are a few other nice features that you'll find really handy.

To start with, the iPhone will alert you automatically if there is an update available, and of course you'll be able to download and install it quickly and easily.

Then, based on the applications you've already downloaded, the built-in Genius app will make recommendations for other iPhone apps, once it gets to know what you like.

And if you end up downloading so many applications that you can't find anything, then you can use iTunes to organise them for you.

Of the literally thousands of apps that are available via the Apple App Store, some are free, while others will cost you some money.

You can, of course, buy these apps as and when you want them, but what if you also want to buy movies, ringtones, music, etc.?

All of that could cost you a fortune, over time.

That's where services such as MyPhone Express are really great - for a very reasonable one-time fee (it's currently on special offer at half the regular price), you can download all of the apps, movies, music, software, ringtones, wallpapers and more for free, for ever, with no limits on how much or how often you download stuff.

And with a 60-day 100% money-back guarantee, what have you got to lose? (Although once you join their private membership and discover what's available, we're pretty sure you will be making full use of their unlimited media downloads for months to come.)