<p>We see an increasing amount of personalized ads and ‘relevant’ content on websites and recommendation lists in online shops. Every time we visit a website that’s hosted in the EU, we’re notified that cookies are saved on our computers that will collect information to improve our online experiences. Everyone seems to be tracking our online behaviour, and the recent cookie-law hasn’t changed anything – it has just made us more aware of it.<br />
And is this only happening online? Our mobile phones can store where we’re going and who our favourite contacts are, and the ubiquitous internet combined with innovative display technologies can turn the whole world into a personalized advertising jungle, with shopping windows and billboards responding to our every move. Fortunately, public displays are not only used for commercial applications, but can also provide information and a means of communication.<br />
Their first challenge is to identify users, who may want to stay anonymous. This rules out log in systems, but can be accomplished in multiple other ways. Facial recognition seems the most obvious one, but this is far from flawless, as this form of computer vision requires complex algorithms and has to be trained for each specific user. And even then, hairstyles and hats that cover or shade part of the face often cause mistakes.<br />
Easier and less computationally intenstive is to connect displays to the users’ mobile devices. Already, users are enticed with free WiFi to log in to stores’ websites and receive personalized ads and offers on their smartphones. Mobile advertising platform Buzz is one of the front runners in this field, hoping to engage customers with content that will then result in more purchases.<br />
The huge amount of information constantly collected from passers-by needs to be processed before information to display on public screens can be selected. Here, providers can take advantage of cloud hosting. Information can be stored in the cloud whenever it’s needed, and all required processing power is shared by multiple computers, so the public displays only need very basic hardware to perform these complex tasks.<br />
The next step is to make public displays interactive, so they can provide users more added value than the latest multi-buy offer. Some developers already experiment with basing output on body orientation and posture, hand gestures, and even facial expressions. These implicit interactions can be used for notifications and help desks, while large touchscreens and the users’ own smartphones can be used to explicitly request certain information or to communicate with screens – and their users – in a completely different location.<br />
With so many users, it is important to find a balance between public and private information. Some information has to be visible to all users on the same display, while other content is only relevant to one person, and should be hidden from the rest. The use of multi-visibility systems makes it possible to control the visibility of all parts of the content independently, while users can still interact with them and change their position relative to the screen.<br />
But more than focusing on sales and privacy, public displays should be used to encourage interaction between users, so they can share information and help each other. The Looking Glass study designed a display that tempts strangers into jumping and dancing together in front of the screen, by mirroring their movements in interactive mini games – a completely opposite approach than the more common subtle ways to avoid social embarrasment by aiming at privacy. In a network that includes your own mobile devices, you can use them for once to connect with other people around you, instead of as a way to hide from them. And those ads? Soon enough, someone will develop an ad block app for public displays, so just ignore them and practice your dance moves with the other guy who’s waiting for the bus.</p>