Do you use a Smartphone, maybe an iPhone, a Blackberry or an Android phone? If so, you’re the target market for one of the many applications that can use GPS to determine where you are and share the information with your friends. The problem with these applications however, seems to be that they have limited lasting appeal which could be a problem when one looks at their market penetration. So, if you’re thinking about investing in one of these firms; it’s worth waiting to see if someone can develop a way to keep the market engaged. In the meantime, it would be better to put your money in psoriatic arthritis treatment or exotic investments, you may get more joy from there.