Customers who use Citibank's iPad bill-paying app might want to pay closer attention to their bank statements: A technological glitch recently caused the app to charge an undisclosed number of customers twice for bank payments.
As early as last summer, Citibank received anonymous complaints, sent to the Apple App Store, about the double charges, according to Andrew Brent, a Citi spokesman. Months later, in late December, the bank detected that its app was to blame for problem. Since then Citibank has alerted affected users and reimbursed them for extra charges and any fees incurred.
Brent attributed the lag between when the company first found out about the issue (in July) and when officials began alerting customers (in December) to the small number of complaints involved. One user had anonymously reported in July that a charge was duplicated as a result of double tapping the screen, according to Brent. He added that there was nothing to suggest that the incidents were linked to the iPad app itself.
Citi later discovered that the app had been programmed to reattempt any transaction disrupted by a network error on the first try. The bank launched an update to its iPad app on Jan. 31. The glitch was first reported by The New York Times on Thursday.
The issue affected less than 2 percent of transactions made via the iPad app, according to Brent. He declined to disclose the number of customers who use the bank's iPad app and how many people were affected by the glitch.
"We take seriously the functionality of our products and services as well as the satisfaction of our clients," Brent stated in an email. "Upon discovering a technical bug in our Citibank for iPad app had caused a limited number of clients to encounter duplicate payments and/or transfers, we immediately fixed the technical issue. Even more important, we have reached out to clients who were impacted to ensure their individual situations are resolved completely."
Citigroup -- which aims to be "the world's digital bank," according to Bloomberg -- has encountered a series of tech glitches in recent years. Two-hundred thousand Citibank credit card holders fell victim to a hacker attack last June that exposed customers' personal data.
In 2010, Citigroup admitted that the bank's iPhone app stored users' confidential information on their phones, making the data vulnerable, according to the Wall Street Journal. The bank subsequently released an updated version of the app that it said patched up the glitch.
According to American Banker, 25 percent of all mobile banking apps earned a "fail" rating as a result of security flaws.