The latest research report, this time from Marin Software, has uncovered a fascinating statistic: mobile devices will account for half of all paid search clicks by December 2015 if the current growth rate is maintained.

It’s certainly a prevalent trend. The research, which asked the opinions of brands and advertisers managing over $6bn in annual online spend, also found that the rate of cost per click (CPC) was faster on mobile than on desktop – with tablet CPC moving ahead of desktop CPC in some regions.

The report also notes that consumers “became increasingly comfortable with mobile commerce” in 2013, paving the way forward for continued growth in 2014 and beyond.

Between January and December 2013, the percentage of mobile paid clicks went up steadily in both the UK and the rest of Europe. The figures of 12.1% for smartphone and 12.3% for tablet in the UK at the start of 2013 leapt to 20.6% and 22.8% respectively by December. Growth in the rest of Europe was a little slower, but still pronounced – 5.1% to 7.7% for smartphone, 7.3% to 12.5% for tablet.

Last year the average click through rate (CTR) across devices showed a marked trend for mobile. In the UK smartphones saw the most CTR at 5.71%, followed by tablets (3.85%) and desktop (2.59%).

It was the same result across Europe, although less pronounced – 3.83% for smartphone, 3.63% for tablet and 3.02% for desktop – as well as the US, where the most popular device was again smartphones, with 3.75% CTR.

Globally however, the results told a slightly different story, and shed light on different countries’ susceptibility to advertising.

India gave the highest CTR scores with 5.7% on tablet, 5% on desktop and 4.8% on smartphone – yet this contrasted strongly with lowest performers Mexico, whose surveyed users only generated a 1.1% click rate on tablet, compared with 1.2% for desktop and 1.7% for smartphone.

There were some interesting elements of the global scores, in particular the disparity in China’s userbase; only a 1.5% CTR on smartphone but a 2.9% return on tablet.

The report also put together a best practice guide for best optimising mobile ad campaigns. The top two ad positions on smartphone are vital, according to the report – across all devices CTRs drop 50% after position two, from 5% to 2.4%.

Similarly, the report urges brands to look at mobile UX – “advertisers should ensure that all parts of their conversion path are well-optimised for mobile devices” – as well as tracking the conversations on mobile, such as click-to-call and store-locator.

The overall consensus, though, is clear: mobile is a huge area for search and advertising spend – and soon enough, it could be the only area.