Nowadays, the most of the navigating solutions operate on the client side, eg. on your PDA or GPS handlet. Typically, You buy the navigation software and a set of maps. Some of the biggest trades of this kind are Tom-Tom and via Michelin. Day by day, your "static" map expires, more and more details get obsolete. So You need to look for some map update, for which You likely have to pay, too. These maps not only loose their up-to-date accuracy, but require strong processor and other hardware elements to handle the large size of data. Is it a good solution? Do You really need to keep a cow if You want a glass of milk? Having a look at the newcomers, with client-server architecture, I am not sure at all.
What does client-server architecture mean when speaking about mapping solutions? There is a small application on the client (e.g. Your PDA or cellphone), with on-line connection to a server. The client application is responsible to get position data (from an outer GPS receiver, or from the carrier), and to send it to the server along with requests like route planning to a particular destination. The server receives these info, calculates the route, and sends back a small map tile covering the current position, and some coded instructions that the client turns to speech navigation ("at the next corner, turn right"). This architecture allows access to the latest maps, and enables dynamic stuff to take into account, like the actual traffic situation along the route. Much smarter, isn't it? To be correct, client side solutions might be completed with TMC services - traffic info transmitted on radio frequency. With this stuff You can at least be alerted when Your route is likely to jam, and the application may start recalculating the route. But You still have to buy huge maps that get expired day-by-day. And the client of a client-server solution is typically so small that any newer cellphone is able to run it. Check it out at www.nav4all.com, or www.wayfinder.com.
I assume now You can feel the trend of how personal navigation evolves. But what's next?
Google has extended the functionality of their mapping solution to web search-based services, and provides free client software for different mobile platforms (J2ME, Palm, Win Mobile) to reach their service. You just visit http://google.com/gmm on your device, and soon You have the proper client application in your hands. With this small applet You can perform web searches to find the location info You look for. It is not only streets, sights, hotels, but dynamic contents from the Internet (like open hours, places recommended by others, etc). The greatest thing is that Google not only delivers the web to your mapping client, but provides free tools to publish individual location contents (favourite routes, placemarks with pictures, etc), that are subject to search, as well. So the range of valuable location info is growing every day, as people share their data by using the My Map function of http://maps.google.com or with Google Earth.
Apparently, it is our common interest to share our kml files and become a part of the Community