"Nearly two-thirds of the unbanked cite poverty as the obstacle to financial access, but about a third also blame the cost of opening and maintaining an account or the bank's being too far away, which means long bus rides for many," said Asli Demirguc-Kunt, the Bank's director of development policy and chief economist of the Finance and Private Sector Network.

In markets like Uganda, mobile money transfer services have become a revenue generator, with players hotly competing for users as margins on voice services have been driven down over the years. MTN Uganda, for example, has more than 2 million registered customers after launching in March 2009. MTN reported recently that US$100 million gets transferred over the service every month.

The four mobile money offerings in Uganda including MTN Mobile Money, Airtel Money, Warid-Pesa and Uganda Telecom's M-Sente are largely similar, allowing registered users to load money into their accounts, make transfers to other users, buy recharge vouchers as well as withdraw money.

The services have been positioned differently though. MTN positioned their offering as a way to send money to others, just like M-Pesa in Kenya.

Subsequent offerings had to find ways to differentiate themselves. Airtel's Money, which was launched in March this year, touts itself as being much more than money transfer, allowing its users that have formal bank accounts to access them.