In the third of Click Online's reports in this month's Africa season, we visit Tanzania where mobile phones are taking the country by storm, although only one in 10 houses has electricity .
An alien landing in Tanzania could be forgiven for thinking that the only business here was the mobile phone. Over the last few years they have completely taken over the landscape.
Mobile signals work in the most surprising places across Tanzania
Some 97% of Tanzanians say they can access a mobile phone, and what is just as interesting, as in many African countries, is how those phones are being used.
Take the island of Zanzibar for example. Here, fishing is one of the mainstays of the economy, supplying restaurants and hotels with fish for the many tourists who visit the island.
Many fishermen now carry mobile phones while they are at sea, and they use them to check market prices.
If there are too many fish in Zanzibar, they sail to Dar es Salaam to get better prices to make more money.
Phones also serve another even more vital use, allowing fishermen in trouble to call for assistance.
As well as the novel uses you find for the phones, it is the sheer extent of coverage that you notice here.
You can get a signal in places so remote you would not even think to turn your mobile on if you were in the US or Europe, such as the smallest villages or even on the slopes of Kilimanjaro.
Call centres make up a huge section of the Tanzanian economy
It is fair to say that the mobile networks are so dominant that the country will probably never develop or need a fixed-line infrastructure.
But recently a debate has been raging as to whether this kind of leap-frogging may have any downside.
It was always assumed that here lurks the spectre of the digital divide.
Since the first internet evangelists emerged from the mist, it has become gospel that for economies to grow and business to flourish, the internet was essential. After all, it was in the West.
So, without landlines, the communications industry would stall, internet take up would be hampered and all kinds of economic horrors would be unleashed.
However, no-one told the Tanzanians about these dire predictions, so they just got on with things.
Call centres have sprung up all over Tanzania. Most people do not actually own phones, so this is how many people communicate.
It is a good business, and once again these phones are connected via GSM rather than landlines.
Others have developed even simpler businesses based around mobiles, such as reselling their air time to others, or make a living sending and receiving text messages.
Mobile phones seem to have created a new sector of the economy, and some now wonder if the emphasis on the internet when looking at the digital divide was wrong-headed.
Len Waverman, an economics professor at London Business School, says: "Even in the more developed parts of Africa, where we thought the phone would just be a toy of the urban rich, it's not.
"It really is a tool for business development, and it's moving across population segments that we really did not before believe would be accessible by these companies."
Research has shown that increased mobile accessibility in Africa is boosting countries' economies in the same way that fixed-line installation in the west did in back in the 1970s.
Len Waverman says: "The digital divide that we thought was really very big between Africa and the rest of us in the Western world is really diminishing, and it's the mobile phones doing it, not the PC."
Inspiring the West
Back in Zanzibar, the latest product by the island's cell phone operator, Zantel, looked traditional, but its fixed-style phone for homes will not connect by either copper wire or even fibre optics.
Mohammed Salim, the CEO of Zantel, explains: "Our strategy is not to go on fibre-optics or copper wires, because that is too expensive.
The lack of fixed lines has not inhibited economic growth
"We are thinking about going through the CDMA, which is a wireless system. That is a very useful and effective way of running out to the rural areas, and to the cities, and much faster than through copper."
Zantel has recently been granted a licence to extend outside Zanzibar and to operate nationwide. To extend their network across the country will cost just half a billion dollars.
Even before their expansion, their subscriber base is growing 25% year on year.
Mobile use in Tanzania and across Africa is gaining momentum all the time, and users continue to confound researchers with their creativity in using the devices.
Already the West has started to look to Africa and the developing world for new ideas as to where to take the technology next.
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