Throughout 2012 we’ve seen numerous studies that highlight the massive difference between shopping behaviours on tablet and smartphones.

The usability of each device should make this obvious, yet they were often – and occasionally still are – lumped together in the mobile category when comparing sales and traffic stats to desktop computers.

This is despite the fact that data published by Adobe in May shows that one tablet generates as many website visits as four smartphones.

By the end of Q1 2012 smartphones accounted for 6.1% of site visits compared to 4.3% on tablet.

However, smartphones only maintain a greater share of website visits due to the lower penetration rate of tablets, with 5x more smartphones shipped across North America and Western Europe compared to tablets.

And new data from Screen Pages highlights the vast difference in conversion rates achieved by each device.

Across 16 of its clients’ websites the average conversion rate was 4.81% between 1 and 15 December.

A decent proportion of the traffic comes from iPads (13.3%) and iPhones (6.9%), and the conversions on each device are remarkably varied.

In average terms, the conversion ratio from desktops was 5.41% – 0.6% higher than the overall average. 

IPads converted less well than desktops at 4.16%, while iPhones bring up the rear with 1.3% – only a quarter as effective as desktops.

Obviously this is a relatively small sample size, but it adds to a convincing body of evidence that proves retailers need to be design their sites and digital marketing campaigns with tablet users in mind.

For example, data from Affiliate Window shows that iPads account for 55% of mobile commerce, compared to 29% on iPhone and 13% on Android devices.

Similarly, data from Monetate shows that the average conversion rate for tablets in Q2 2012 was 3.17%, slightly behind desktops (3.34%) but far higher than smartphones (1.09%).

However Monetate’s report delivered somewhat surprising results for average order values, with smartphones achieving a higher AOV than tablets.

Both iPhone ($97.49) and Android devices ($97.16) drive higher average orders that iPad ($96.80).

This contradicts data from Adobe’s Digital Marketing Insights report, which found that tablet visitors to ecommerce sites spend 20% more than desktop shoppers and twice as much as those using smartphones.

Finally, a report published earlier this week by Kenshoo found that tablets drive the highest average order value at £85.55, followed by smartphone (£77.80) and desktop (£75.93). 

It also revealed that smartphone conversions lag way behind the other devices at just 1%, compared to 4.99% on tablet and 5.16% on desktop.