Research from retargeting vendor Criteo recently found that website visitors who subsequently see retargeted display ads are 70% more likely to convert.

This highlights the highly responsive nature of the audience for retargeted ads, which can result in great returns for advertisers willing to invest.

The first edition of Econsultancy’s Display Retargeting Buyer’s Guide was published last week, highlighting the latest trends in the display retargeting industry, and containing introductory profiles of 15 vendors of display retargeting technology.

Vendors range from the likes of Google and Rakuten Marketing who offer retargeting as part of a broader range of services, to providers of specific retargeting services such as Chango and myThings.

The common ground between these companies is the concept of tracking and serving ads to those consumers who have shown purchase intent.

The buyer’s guide discusses the different forms of retargeting, and some of the latest trends in the industry, before outlining its strengths and weaknesses and giving some tips and pitfalls to marketers looking to take on a retargeting vendor.

A number of industry experts from the featured vendors were interviewed for the guide. Sam Barnett, Founder and CEO at Struq, spoke of the benefits that retargeting can bring to advertisers:

Ad retargeting offers marketers the most effective use of display marketing spend, giving higher ROI and user engagement than traditional display ads. As well as delivering the best performing ads, retargeting gives marketers greater analytical insight into which products are driving sales, which creative elements drive sales, which publishers are driving sales etc.

The result of extensive testing and optimization gives marketers granular insight into what drives performance which they are able to use to make their other marketing channels more effective.

Historically, display retargeting has been desktop site-focused, and used by advertisers in retail sector. However, developments in advertising on devices other than desktop, and in real-time bidding, have resulted in the expansion of the practice into newer channels and sectors.

As a result, retargeting on mobiles is one of the most-discussed trends in retargeting at the moment. Mobile has an ever-increasing availability of inventory as mobile-optimised sites improve and app use increases.

Specialist retargeting vendors have a strong foothold in the desktop retargeting arena, but mobile is still dominated by big mobile apps.

Mobile retargeting has in the past come with a raft of technical difficulties distinct from retargeting desktop ads, due to limitations in the use of cookies for tracking. The range of devices, operating systems and settings means that there is no consistent method of tracking users while using their mobile, let alone across devices.

Technologies such as Drawbridge and Tapad are beginning to be developed that aim to solve this problem for publishers by trying to find patterns in data from mobile and desktop browsing, and matching them to identify users (sometimes called probabilistic device recognition).

Cross-device tracking is a huge boost for display retargeting as consumers are increasingly using multiple devices during the path to purchase, and uncertainty over the future use of cookies prevails.

However, for Facebook, Google and Twitter, the process is much simpler because their users have to sign in, and tend to do so across multiple devices, meaning that they can retarget their users based on their desktop browsing.

Facebook’s ‘website and mobile app custom audiences’ was announced last year, and allows retargeting across their mobile inventory with custom audiences refined by demographics and geographic information.

Twitter also released ‘tailored audiences’ in 2013; enabling advertisers to create audience segments using website and behavioural data, which can then be targeted on Twitter.

Twitter retargeting vendors (including some of those featured in the guide: AdRoll, Chango and Perfect Audience) are now working with Twitter to target segmented audiences with Promoted Tweets or Promoted Accounts.

Laurent Gibb, VP Media at myThings, said of mobile retargeting:

The key growth area is in mobile. Social (FBX and Twitter) is where highly engaged users spend most of their time online. Naturally, it’s a key channel for marketers.

Beyond the obvious benefits of Facebook’s massive reach (our data shows up to 32% exclusive reach) and lower costs, we have found that the social environment also has a positive effect on shopping with a sales cycle three times faster compared to other exchanges (impression to click to conversion).

Mobile retargeting is one of a number of trends discussed in our new Display Retargeting Buyer’s Guide. Others include developments in programmatic RTB, cookie loss and privacy concerns, and growth in newer forms of retargeting including search and CRM.

The guide aims to help companies quickly evaluate vendors, and provides tips (and pitfalls to avoid) to help you find the right display retargeting vendor for your needs.