As mobile banking systems become increasingly popular, some fintech startups have partnered with the Bill and Melinda Gates Foundation to reach the underbanked in developing nations.

Dwolla, a Des Moines payments network, and Ripple, a blockchain network based in San Francisco, were among five companies that recently worked with the Seattle organization to develop a free, open-source banking code called "Mojaloop," which was released Monday. (The companies were compensated for the effort, though the foundation declined to offer specific numbers.) 

The code--named after the Swahili word 'moja,' meaning 'one'--aims to increase interoperability between financial institutions and mobile payments platforms, thereby reaching more of the underbanked and unbanked in areas such as Africa and Asia. At present, some 2 billion people lack access to bank accounts, according to World Bank data, a figure just 20 percent lower than in 2011.

"The reason these people are unbanked is that typically they are remote from any traditional banking branches or ATMs, [and] traditional banks are not well equipped to serve them," explained Kosta Peric, the foundation's deputy director of Financial Services for the Poor, in a phone call with Inc. At the same time, he suggests, many businesses are reluctant to invest in technology that serves the poorer segments of the population and might not produce large returns.  

Mojaloop comes as a growing number of consumers turn to digital wallets as a way to manage funds. Just last week, the payments giant PayPal--which spearheaded online payments and money transfers--surpassed American Express in terms of market value. Nearly half of the U.S. population uses apps to pay bills, make purchases, and send or receive remittances, according to recent Pew research. And as smartphone adoption surges in the developing world, so, too, does mobile banking: Roughly 55 percent of people in India currently use phones to purchase financial products, additional Pew research found.

While digital banking software has proliferated in recent years--particularly in the U.S. and Europe--those products are not always compatible with foreign financial institutions, thus cutting off access to billions of potential customers. In Kenya, for instance, the digital banking startup M-Pesa has helped to lift nearly 200,000 customers from poverty--though it has yet to be adopted in some neighboring countries such as Rwanda and Uganda. 

Peric at the Gates Foundation notes that while there are some alternative systems in place--such as the Bangladeshi 'Bkash'--those systems tend to be incompatible, both with each other, and with financial institutions. "The next wave of innovation that this [Mojaloop] unlocks is that now you can connect not only the mobile money systems but also the traditional banks," he says. 

In particular, the Mojaloop code leverages a technology called Interledger Protocol, which lets financial providers settle funds across different individual systems.

"Interoperability is necessary both for financial inclusion and market maturity, but it is a complex thing to achieve," explained Benno Ndulu, governor of the Bank of Tanzania, in a prepared statement. "We are excited to explore implementation of this because of how it can simplify that capability for businesses and governments, and speed up access to financial services."