This is Business Daily on the BBC World Service with me, Jane Wakefield.

Coming up, what's lurking on the cheap smartphones bought by millions worldwide?

It could prove something of a surprise.

Mobile home ecosystem is just like a large city.

Every city has crime.

Every city has their dutchy area where people can buy stuff for in the back of the truck.

This is the digital analogy to that.

And how many lower-income Africans are the ones most at risk from the corrupted technology?

But the problem is most of these users of these forms are semi-illiterate or illiterate.

They have no idea about, you know, cyber security and they don't even know how to solve it.

Business Daily on the BBC.

Getting a mobile phone can be a big investment and it quickly becomes the place where your whole life is stored.

From social networks to chat apps, banking, shopping and email, everything is there.

So imagine investing in a phone, taking it out of the box without any clue that lurking on it pre-installed is malware that could seriously hit your bank balance.

Millions of Africans are buying cheap Chinese manufactured smartphones for around $30 to $40,

which can be a huge investment.

And now it seems that thousands are getting ripped off.

Last month's security firm upstream noticed an unusually large number of transactions

coming from phones based in countries like Ghana, Ethiopia and South Africa.

All the phones were the same brand, a company based in China which offered cheap handsets,

which we'll talk about more later.

Further investigation revealed that more than 50,000 of these phones had a piece of malware pre-installed on them. The ex-helper triada malware is invisible to the user, but acts as a

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