A growing number of shoppers apparently need only the briefest of breaks before diving back in, especially if they can log in to shop.

IBM found that online shopping jumped 16.4 per cent on Christmas Day over last year, and the dollar amount of those purchases that were made using mobile devices leaped 172.9 per cent.

IBM tracks shopping at more than 500 websites other than Amazon.com, which is the largest. It found a huge increase in the number of shoppers making their purchases with iPhones, iPads and Android-powered mobile devices.

In fact, nearly seven per cent of all online purchases were made using iPads, just 18 months after the tablet computers were released by Apple Inc., said John Squire, chief strategy officer for IBM's Smarter Commerce unit.

The online uptick continued on Monday. As of 3 p.m. ET, shopping was up 10 per cent over Dec. 26, 2010. And the expectation was that the pace of buying would increase as the day wore on and consumers clicked on sales at various retailers.

Squire said consumers were chasing sales on both Sunday and Monday. The data did not show what portion of purchases was made using gift cards.

Canadians boosted spending by 15.4 per cent on Cyber Monday (Nov. 29) compared to dollars spent during the comparable period in 2010, Moneris Solutions reported earlier this month.