A recent study from the World Bank Development Research Group found that more than half the world’s adults – 2.5 billion – are unbanked. With only 10 million of these unbanked individuals living in the U.S., the vast majority of them live in developing areas such as India (40% unbanked) and Africa (80% unbanked).

With such huge numbers of unbanked individuals, clearly there’s not going to be a sudden shift where the unbanked suddenly sign up for services at mainstream banks. That’s why mobile money makes so much sense and is expected to grow so rapidly in the coming years.

In sharp contrast with the number of unbanked is the number of adults worldwide that have a smart phone. A 2011 infographic from Microsoft Tag showed that over 1 billion of the world’s 4 billion phones are smart phones, which provides an immense opportunity to get the unbanked on board with financial services from paying bills to transferring money.

For Mobile Money to become a reality for the world’s unbanked, operators and merchants need to be able to provide services that are reliable and sustainable. The true key to success with mobile money is offering services that meets subscriber needs and are able to keep pace with trends. Consumers are moving from not really using financial services so solutions need to dead easy for them to use and immediately create a value add.

A great example of Mobile Money designed with customer needs at the core, and focused on value is Digicel’s work in Papua New Guinea. It has been recognized with awards for its innovation and the cellmoni service offers multiple options for consumers by transforming Digicel mobile phones into electronic wallets. Consumers can then deposit or withdraw cash using their mobiles at a nationwide network of agents, receive salary payments, pay bills and transfer money to any Digicel mobile in the country. There is also a focus on cash safety, which is key with the mobile money scams that are popping up around the world.

Mobile money is truly providing a revolution in financial services bringing possibilities to individuals that they’ve never had before. But ease of use and reliability need to placed at the core of services to ensure its success.