Mobiles and tablets accounted for 12% of all paid search clicks in the UK during December, according to new data from Marin Software.

This represents a 49% increase in click share as a percentage of the total since October.

The Quarterly UK Online Advertising Report found that, over the same period, spend share of mobile and tablet devices increased by 29% to a 7.5% share of overall search spend.

Marin said the disparity between mobile click share (12%) and mobile spend share (7.5%) highlights favourable performance conditions for mobile advertisers.  

Relative to desktop search, volumes are growing faster than budgets, resulting in less expensive clicks on mobile campaigns.

Marin vice president of marketing and partnerships Matt Lawson said: “The budgets for mobile search advertising still lag user adoption of devices. Given this gap, we expect mobile search to see continued investment as advertising dollars chase consumer behaviour in 2012.”

Across all devices, paid search click volumes increased 43%, click-through rates increased 24% and cost per click decreased 5% during Q4 2011 on a year over year basis. 

Marin also added that the combination of improving CTRs and declining CPCs point to significant efficiency gains for advertisers over the past year.