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In Brazil, a start up company, that was founded and funded by China, is helping customers save money when they make mobile phone calls.

Cell phones with multiple SIM cards are popular in Brazil. They give callers a choice of different services which can save them money depending on the network. But the phone number alone does not identify the cheapest network so people don't often know which SIM card to use.

Chinese entrepreneur Zhen Zhang noticed the problem when he came to study for an MBA in Brazil - and saw a business opportunity in it.

Understanding the needs of consumers and fulfilling them is key for the success of pretty much any business but probably even more so in the case of startups. And saving money is something every consumer wants.

He launched a startup company and created an app - called Mobobox - to help consumers decide which network to use for each call.

The business, aimed at lower middle class consumers, already claims to have signed up two million active users.

"There are too many carriers in Brazil so this app is helpful because it sorts my phonebook according to the operator so I know which SIM card to use," said Mobobox user Fabio Malagoli.

Mobocity's software development happens in China and most of the investment comes from there.

A local team handles the operations and market development in Brazil for this and other projects.

"The most important thing for our Chinese investors now is how many users we manage to have connected to our platform. They are not looking to make money right know but they are really interested in how much engagement we can get with our users," said Talita Lombardi, COO of Mobocity.

In these tough economic times in Brazil, every cent counts. And helping consumers to save them money can be a good business.