As smart phones explode in popularity they are prompting the development of new kinds of social media services, notably "location-based services" that reward people for actively sharing their physical locations, a process called "checking in". Now a new wave of similar services will accomplish this automatically, with little or no input from us. Does this demonstrate our newfound comfort with surveillance, and are we getting enough in exchange for the privacy we're discarding?

Briefly, location-based social media services are a rapidly emerging kind of application largely driven by smart phones. The use of these apps on smart phones helps connect the web to the physical world: the stores, places, and communities around us. Some of these services are game-like, such as Foursquare and Gowalla. Others are tied into review sites like Yelp, or map services like Google Buzz, Places, and Maps. Twitter and Facebook are also actively getting into the location-based services game, adapting their services and apps to take advantage of the world around you and help you connect not only with friends, but the places and business that are nearby.

This still begs the question as to why you would "check in" and how does automatic checking-in work?

Some apps make it fun - adding value to your experience of the app - but it also lets your friends know where you are so they could join you (or sympathize with/envy you). With other services the (possibility of) rewards provide incentives for people to share their location. For example, in Foursquare you may receive discounts if you're a Mayor or special badges that might be symbolic or act as digital coupons.

Automatic check-in has the potential to transform the location-based service world for several different reasons. Part of the problem with the first wave of services was that you had to remember to "check in". Worse, it sometimes feels awkward or nerdy to arrive somewhere and then open your phone to tell the world you're there, a mitigating factor for an app's popularity.

Automated services promise to improve ease of use and access to potential rewards. One new startup called Shopkick detects anytime you walk into a (participating) store and rewards you just for visiting. It gives you more rewards if you buy something and still more if you return with friends. The rewards are based on a kind of virtual currency that you can redeem for store gift cards, or transfer to Facebook credits.

Another startup called DailyCandy detects when you're close to a participating store and offers you a special digital coupon to enter and purchase something. Rather than overwhelm potential users, DailyCandy wants to distinguish itself by focusing on quality establishments that it feels its users will love.

Auto-location and auto-check-in is tricky and its rate of success depends on the technique being used. With services like Foursquare, which have auto-check-in add-ons, accuracy is necessarily very poor. For the most part phones have limited capacity to detect location - even GPS-capable phones are only able to pinpoint location within several hundred metres, due to building interference and other factors. In a dense urban area your phone would be automatically checking you into dozens of places you're relatively near but obviously not at. There's just too much potential for misunderstanding - "mis-check-ins".

Shopkick sidesteps this problem by employing an entirely different check-in method. Their approach is to broadcast a noise in participating stores inaudible to humans but capable of detection by a smart phone, provided it's running Shopkick. So the moment you walk into the store it detects that noise and checks you in. In theory, for a big department store, they could register where in the store you went by what noises the phone picked up. It's an innovative approach to location-based services, relying as it does on auditory detection rather than GPS or tower triangulation.

What does this mean privacy-wise and surveillance-wise?

We're seeing the further commodification of privacy - for the right incentive, we are clearly willing to be monitored. This began with initiatives like Air Miles where when you buy something at a store and someone asks, "Do you have Air Miles?" really what they're asking is, "Would you like to give up your privacy and have this purchase tracked in exchange for a few points in a virtual currency?" What we're seeing now is the expansion of this kind of data-mining campaign to mobile devices.

The key difference is that mobile devices are able to track such vast amounts of information about what we do and what we consume that we should get far greater rewards for giving up our privacy in the mobile domain. We'll have to see if and when that happens, but the competition amongst these various location-based services certainly leaves that possibility open.

It is easy to imagine a world where these mobile tracking tools will be automatically included in the phone package - it's just a matter of finding a way to frame or sell that proposition. We've always imagined it coming in the form of a "free" mobile phone. You get the device, and get to use the device, for free. However, everything you do is tracked/monitored and you have to listen to and watch the occasional advertising as a means of paying for the phone. It's your time, attention and privacy that you're selling in exchange for the "free" mobile device.

These concerns are relevant for many new technologies, but We are particularly interested in how location-based services will converge with the mobile device as digital wallet, which can act as a credit/debit card/device. As we have ever more powerful computers in our pockets, technologies like these will flourish and we will need to learn to determine the most efficient and economic ways of using them to earn rewards without giving away too much of our privacy.