A new app will allow users to control nearly every aspect of how their credit or debit cards are used directly from their smartphones.

CardControl is a service that aims to reduce the prevalence of credit card fraud by letting users set controls that determine how each card can be used from their smartphone. The hitch is that banks must opt in to the service before individuals can use it.

"You use your card at a merchant the way you normally would, but you use your phone as a remote control to determine when, where and how the card can be used," Ondot's CEO and cofounder Vaduvur Bharghavan told Mashable. "We're putting intelligence into the card without touching the card in any way."

The service offers users a variety of in-depth controls to manage how cards can be used. At the broadest level, a card can be simply turned on or off. Specific types of transactions, like online transactions, can also be enabled or disabled. Bharghavan says this feature is particularly handy to parents, as they can determine what types of transactions their children can make.

Users can also set specific locations for where transactions can be made. Consumers can set a specific geographic area where purchases can be made or select "around me," which ties transactions to the location of their smartphone. If this setting is enabled, a credit or debit card will only work when a user's phone is nearby.

CardControl allows users to set controls for exactly how and when their credit cards can be used. Image: Ondot Systems

Ondot, the startup behind CardControl, partners with credit card processors to offer banks CardControl's technology. The company currently works with four major processors who together process transactions from 10,000 banks and credit unions in the US. Banks can either integrate CardControl's features into their existing apps or offer it as a standalone app, though the company says it expects most banks will choose to integrate the features into their existing apps.

Bharghavan said banks are particularly excited about CardControl's potential to reduce credit card fraud. Lone Star Bank in Texas, which partnered with the company early on to offer CardControl to its customers, said the app reduced its losses due to fraud by 60% in one year.

It's up to individual banks to offer CardControl to customers but people can find out if their bank offers the service by emailing Ondot.