Mobile shopping grew 19-fold in 4 years, mostly on iPads and iPhones

In the past four years, mobile shopping in the U.S. has grown 19-fold, according to a report issued Monday by Custora, an e-commerce platform that works with retailers from Ann Taylor to Etsy.

Among its findings:

Mobile e-commerce in the U.S. is a $40 billion market, up from $2 billion in 2010. More than a third of visits to online stores now come from mobile devices, up from 3% in 2010.
E-mail marketing does “surprisingly well” driving purchases on phones and tablets; social media not so much.
The iPhone accounts for 53.6% of orders made by phone. The Pad accounts 79.9% of tablet orders, but Samsung and Amazon (AMZN) are gaining with 12% and 4%, respectively.
Mobile phone purchases tend to be small-ticket items. Most shoppers wait until they get to a tablet or computer to buy the expensive stuff.

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Custora says it based its findings on U.S. e-commerce data from more than 100 retailers, 70 million customers and $10 billion in transactional revenue. The data are available for download here.

Below: Custora’s mobile phone and tablet charts.