Since mobile devices seem to be the ubiquitous form of communication these days, it was only a matter of time before a slew of services began rolling out that utilized the everyone-has-it-with-them attribute to the fullest.

The most appealing factor to marketers and developers alike is the fact that you can incorporate location-aware services into mobile devices to create some rather unique and useful applications.

When you throw location-awareness into the mix, it opens up things like mobile social networking whereby one can always know where their friends are at all times, as well as unique mapping which can tell exactly where you are and point you in the direction of whatever you desire.

With the introduction of the iPhone, location-aware applications started showing up more and more. The iPhone, which utilizes Skyhook's location-awareness platform, uses a combination of wifi, cell-tower, and GPS location data to know a user's position at all times. But how does it work?

We all know GPS uses satellites to get its location-fix, but wifi and cell-tower location uses a different method. Cell phones constantly ping a signal to nearby cell towers basically letting them know its there. With this signal, you can use an algorithym to calculate the distance between 3 different cell towers within range of you at all times, and then use that data to compare against a central database of cell-tower IDs. Every cell tower in the country has a unique cell ID, once your device knows the IDs of the nearby cell towers, it can search the database and return your position.

It may sound complicated, but it makes way for location-aware services to any and all cell phones made no matter the make, OS, or anything else. Before GPS makes into all devices, it makes for a semi-accurate location-source.