Happy birthday iPhone - the device that has come to symbolise the smartphone more than any other celebrated its fifth birthday on Friday.

In just five short years, the device has come a long, long way, with revenues greater than the GDP of Kenya, Serbia, or Costa Rica.

Meanwhile, enough iPhones have been sold to circle 70 per cent of the globe if placed end to end, and the iPhone makes up nearly 75 per cent of all smartphone sales by value.

The iPhone has created a whole multi-milion dollar industry in which 30 billion copies of half a million apps have been downloaded, creating, it is estimated, some half a million jobs.

The dominance, however, is not necessarily set to last. Google's Android operating system is catching on, and Samsung are beginning to come out of their shell in unit sales terms with their phenomenally successful Galaxy series.

Apple, however, are not resting on their laurels, with a new iPhone, the successor to the 4S, expected later in the year.