Mobile search spend in the UK increased by 250% for Q1 year-on-year (YOY) as traffic on mobile devices increased four-fold, according to data from Adobe.

Mobile now accounts for 11% of all UK search spend compared to 8% in the US.

Of this, tablets alone accounted for 4.25% of UK search spend.

But despite this boom, Adobe’s Global Digital Advertising Update shows that overall search spend only increased by 2% in the UK compared to 16% in the US.

This is lower than the 30.3% YOY increase in US search ad spend reported in IgnitionOne’s Global Online Advertising report, but still shows that the industry is experiencing strong growth.

Adobe’s report suggests that the relatively low increase in UK search spend “reflects the fragile state of the European economic recovery.”

Director of new product innovation Jonathan Beeston said that the 2% growth is also down to a strong performance in Q1 2011.

Last year the search industry saw a huge growth due to a recovery in the travel industry, so there wasn’t as much room for a spend increase this year.”

The massive increase in mobile spend is attributed to disproportionately low cost per click (CPC) on tablets compared to desktop despite comparable conversion rates. 

As a result mobile and tablet advertising investments become more appealing to advertisers in the short term.

Looking at the search engines, the report found that Google CPCs fell by 5% YOY, while Bing/Yahoo CPCs increased by 18% as marketers took advantage of better return per click.

Consequently the Bing/Yahoo advantage over Google in terms of ROI no longer exists.

Beeston says that the recent Search Alliance will have benefits for marketers, not least because the Microsoft’s adCenter is easier to work with than Yahoo’s UI, but ultimately will do little to overcome Google’s market dominance.

It won’t affect market share from a consumer perspective. The real challenge is how to take on Google in Europe and increase market share, so it will be interesting to see what they’ve got planned.”

Another key trend highlighted in the report is the growing spend on social, particularly within Facebook.

Facebook spend increased by 93% YOY, which on a relative basis represents 3% to 5% of search spend – indicating that it continues to be a strong, emerging market.

Beeston says social spend is likely to increase in 2012 with the report predicting that brands will generally see a 100% increase in fans this year.

I think Facebook is going to continue steaming along, especially as advertisers are really getting a handle on what it can do for their business. More and more of our clients are now properly tracking their Facebook activities and they can see the positive impact it’s having.”

He said that as Facebook rolls out mobile ads this will likely increase social ad spend even further.