Smartphone revenue was higher than tablet revenue, according to the latest MarketLive Performance Index.

Retailers saw significant year-over-year gains in mobile commerce during the third quarter, according to a newly released survey, the MarketLive Performance Index, from e-commerce technology and services provider MarketLive Inc. MarketLive analyzed domestic revenue and traffic figures from its retail clients, which included retailers that operate stores and e-commerce sites as well as online-only retailers across several sectors—Beauty & Health and Apparel, Footwear & Accessories, for example—over a 15-month span.

Shoppers on smartphones spent 233% more in the third quarter of 2015 than they did during the same period last year. The MarketLive index reports revenue percentage changes, not dollar figures.

A notable statistic was the shift in usage from tablets to smartphones. Smartphones accounted for 29.8% of e-commerce traffic during the quarter, up from 26.7% in 2014, compared with 12.4% on tablets, a decline from 15.0% of traffic in 2014. Smartphones also narrowed the gap with tablets when it came to average order size ($137.48 compared to $151.41), although customers are still spending more on average on their desktops ($161.57).

Another shift in shopping behavior: smartphones’ share of revenue was higher than tablets’ share at 13.7% versus 12.5%. In 2014, share of revenue was 9.7% for smartphones versus 13.1% for tablets.

"We're seeing smartphones continue to exert their influence on every category of retail,” MarketLive CEO Ken Burke said. “It doesn't matter if you sell computers, clothing or couches, shoppers want to buy your products from the convenience of their phones. As an industry, if we can remove the last few hurdles around mobile checkout, we'll see mobile shopping become truly ubiquitous."

BY MATT LINDNER | Research Analyst | mobilestrategies360