What's next for newly public BankMobile

Stephen Greer, senior analyst at Celent, a research and advisory firm in Boston, said it will be easier for BankMobile to raise capital as a publicly traded company than directly through investors.

He says many challenger banks funnel their resources to customer acquisition, where the costs can be high, but stall at the next step: diversifying their products. Challenger banks need customers to be profitable but need a varied set of products to become viable.