So to find out whether there’s any basis for combining paid search campaigns for desktop and tablets, here is a summary of seven reports that look at the differences and similarities between the two devices in various metrics including conversions, CTR, CPC and average order value.

And for more information on this topic checkout our new Paid Search Marketing (PPC) Best Practice Guide, which covers everything you need to know about paid search advertising.

Conversions are similar, but huge difference in average order value

  • A report from Kenshoo that analysed the performance of different devices in paid search throughout 2012 found that tablets deliver a similar conversion rate to desktop, but a markedly different average order value.
  • Conversion rates on tablet were 5.85%, which is similar to desktop (6.53%) but massively different to smartphone (1.59%).
  • However the average order value achieved on desktop was £73.78, which is very similar to the AOV achieved by smartphones (£71.98). In comparison, tablet devices deliver a far higher AOV of £88.84.

  • It’s interesting to note that CPCs are also quite varied, at £0.36 on desktop compared to £0.25 on tablet and £0.17 on smartphone.

Tablets conversion rates are 1% lower than on desktop

  • In December last year ecommerce agency Screen Pages published data from 16 of its clients which again served to highlight the big 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.
  • The conversion rate from desktops was 5.41% – 0.6% higher than the overall average – while iPads converted at a rate of 4.16%, more than 1% lower than desktop.
  • Unsurprisingly, iPhones proved to have the lowest conversion rate at just 1.3%.

Maybe they are one and the same?

  • Data from Monetate found that in Q2 2012 conversion rates on desktop and tablet were very similar at 3.34% and 3.17% respectively.
  • Smartphones achieved a conversion rate of just 1.09%.
  • Monetate’s report analysed a random sample of more than 100m online shopping experiences using ‘same store’ data across each calendar quarter.

Conversion rates converge on Cyber Monday

Tablet vs. traditional (desktop) conversion rates on Cyber Monday

Tablet shoppers spend 21% more

  • A study by Adobe published in January 2012 – which does mean the results are somewhat dated – found that tablet visitors to ecommerce sites spend 20% more than desktop shoppers, and twice as much as those using smartphones.
  • The AOV for tablets in 2011 was $123, compared to $102 for desktop and $80 for smartphones.
  • The report, which took its data from 16.5bn visits to more than 150 retailers, also found that the average conversion rate via tablet was 2.3% compared with 2.5% for desktop, while mobile lags behind on 0.6%.

Smartphones achieve highest paid search CTR

  • According to a report from Marin Software desktops actually achieve the lowest CTR in UK paid search at just 2.29%, compared to 3.93% on tablet and 5.87% on smartphone.
  • And though the same is true of the Eurozone, the difference is less pronounced – smartphones achieved a CTR of 4.78%, compared to 4.48% on tablet and 3.1% on desktop.

  • However the report also shows that CPCs on desktop and tablet are almost identical at £0.30 and £0.28 respectively, while smartphone CPCs are just £0.15.
  • Marin’s report shows that smartphones achieved a conversion rate of just 1.6% in the UK during 2012, compared to 2.6% on tablet and 4.1% on desktop.

Marketers stuck between a rock and a hard place

  • Digital marketing firm Website Publicity raised its own concerns in a blog post that highlighted data from 10 of its ecommerce clients.
  • It found that for each business included in the sample tablet conversion rates we noticeably lower than on desktop and suggested that this is also true of the rest of its client base.
  • In the test sample one client’s ads to tablets converted just 20% below desktop, but the overall average was a 40% lower conversion rate.

  • The result is that marketers are left with two options: pay too much for tablet traffic, and see their return on ad spend (ROAS) decline, or bid lower for desktop traffic to maintain their ROAS and watch their ad positions, traffic, and overall sales decline.

In conclusion…

Going purely on the data from these surveys, it seems that in some instances there does appear to be a convergence between desktop and tablets in terms of CPCs and conversions, while others show that the two devices deliver wildly different results.

But the inconsistency found in these surveys only serves to underline the fact that Google’s decision to combine PPC for desktop and tablet in Enhanced Campaigns makes it difficult for marketers to properly optimise their campaigns based on different user behaviours.