Mobile banking is not just for the wealthy — far from it.

A report from the Federal Deposit Insurance Corporation released today says just the opposite: the underbanked are greater users of mobile banking services than those with higher incomes. But the underbanked often rely too much on their mobile devices to meet their banking needs, according to the FDIC, and financial institutions should make extra efforts to help these customers meet their financial needs.

The FDIC defines “the underbanked” as customers that use alternate financial services such as check-cashing in addition to traditional banking accounts, which the majority of underbanked customers have. In other words, traditional financial services are not completely meeting the need of underbanked customers. The FDIC numbers the underbanked at more than 24 million.

A whopping 90.4% of underbanked consumers have access to mobile phones, and 71.1% of those have access to smartphones, according to the FDIC survey cited in today’s report. This compares to 86.8% of fully banked households with access to a mobile phone, and 67.8% of those households with access to a smartphone.

The deep penetration of mobile phones makes the underbanked greater users of mobile banking than the fully banked. 42% of underbanked consumers have used mobile banking on a smartphone in the past year compared to 34% of fully banked customers.

The FDIC hailed the mobile device as the tool for financial inclusion, but also raised concerns that over-reliance on the device means the underbanked are missing out on a number of benefits. For one thing, the frequent brief interactions encouraged by a mobile device mean the underbanked rarely experience face-to-face interactions in the branch and fail to learn about additional products. The FDIC, therefore, encourages banks to meet with underbanked customers face-to-face, but doesn’t specify how this should be accomplished beyond saying mobile should be integrated with broader strategies such as “consumer engagement.”

Case in point, Fifth Third Bancorp, for example, recently announced that it is looking into offering micro-loans again. A previous attempt of the bank’s to offer microfinancing was scuttled by regulators due to concerns over disparate impact.

The complete report can be viewed here.