Some bank customers would actually pay to use their lender’s mobile app, according to the results of a new survey – and customers of Charlotte-based Bank of America are the most open to the idea. Research company SNL Financial last week released the findings of the survey, which asked customers of nine large U.S. banks if they would be willing to pay $3 a month to keep using their banks’ apps. Among Bank of America customers, 33 percent indicated a willingness to pay the fee, the highest percentage for any bank. Citigroup customers came in second, at 31 percent. It’s not clear from the report why Bank of America’s customers were more receptive to the fee.