Online payment company PayPal processed nearly $4 billion worth of mobile payments in 2011, an exponential increase from the previous year.

To put this figure in perspective, the company processed $750 million worth of mobile transactions in 2010 and $141 million in 2009, David Marcus, vice president of PayPal Mobile, said at the Consumer Electronics Show.

The huge growth in mobile payment volume is the result of an overall increase in mobile commerce, combined with the availability of more useful mobile payment apps, Marcus told VentureBeat.