The one problem with most sat-nav devices is that you need to constantly keep them up to date. Roads close and new ones open, layouts change and speed cameras mushroom like the spores of some particularly virulent fungus. If you don't upload map updates to your device you're likely, at some point, to end up being instructed to go the wrong way down a one-way street or to take the long way round when a much faster route is available. That's why I like TomTom's Mapshare feature so much - it allows users to update each other on major road changes for free. And it's also a reason why 'live' phone navigation software such as Telmap, and Wayfinder 8 - on review here - work well.
Instead of storing all the map data locally, Wayfinder's maps are kept on a server and, just like Google maps, portions of it are downloaded as and when requested. Not only does this ensure that the maps are kept bang up to date automatically, but also that storage requirements are minimal. All you need to install on your phone is the application, so the rest of your space - especially critical if you own a phone with no expansion slot - can be dedicated to video, picture and music storage. Route calculation, too, takes place entirely on external servers, rather than relying on the possibly low processing power of your handset.
It's available on a wide range of handsets too - not just Symbian S60 and UIQ devices, but also Windows Mobile 6 Professional handsets and Blackberries too (you'll find the full list on the Wayfinder website). And if you find you don't like the thing, it won't necessarily have cost you the earth - the cost of a 12-month subscription is £40 and for three years' worth it's a mere £48.
Furthermore, it's stuffed with clever features. Log into the companion website - MyWayfinder - and you can add 'favourite' destinations without having to punch them in laboriously on your phone's numeric keypad. The application on your phone will then sync with the site and download the locations for use locally. There's a Facebook app too that you can use to publish your location, and a Google Earth tracking utility too. Switch the latter on (and the tracking mode on the phone) and all your movements from the past week will be recorded in a downloadable KML file with the track overlaid onto the map. What's more, you can also download portions of the map from the MyWayfinder website and install them locally - useful if you know you're venturing into an area with a weak mobile data signal.