Mobile marketing - May people have heard of geofencing. In geofencing, you can target digital ads to be delivered to devices that are in a particular area - even down to a particular building. You can go further to target devices that have been in that building with some level of frequency and where those in the building have been visiting certain types of sites (using cookies). Of course, wearables offer a new level of tracking - although probably not anything more than we already had with smartphones. Many people say they don't want to be tracked, yet rely on location-based services on their phones.

You see then what we're getting at here. These tools work for the marketer, but they have implications for the public. But beyond these obvious ethical/privacy concerns, what other issues are there? Please don't just discuss the privacy and tracking concerns.