There's a lot of navigation tech doing the rounds at the moment. Quite apart from the (at last count) eight million rival mapping software packages there's all sorts of compact outdoor-recreation oriented GPS receivers, GPS-enabled PDAs and things around the place. One of the more interesting developments, though, is Augmentra's ViewRanger software, which puts digital mapping and virtual landscapes on your mobile phone.

Obviously most phones don't have GPS receivers built in, but you can get relatively inexpensive GPS units with Bluetooth gubbinses in them so that they can talk to your phone from a pocket or your pack. With one of those, a suitable phone (a Nokia smartphone is your best bet) and ViewRanger, you get a graphical representation of what you ought to be able to see in front of you on your phone's screen. It moves about as you do, and all the summits, towns and other landmarks are labelled. It also features the familiar OS Landranger mapping with points-of-interest overlays.

It gets better, though. Select one of those points of interest and you're connected to the ViewRanger server to see what other people have said about them or to upload your own photos or comments. The software also lets you virtually "jump" over the hill in front to see what's in the next valley and do relatively mundane things like tell you exactly where you are.

Viewranger will still do a lot of useful things without a GPS to talk to, but obviously it's a little bit clunkier because you have to tell it where you are manually. Then again, that's no more onerous than keying in someone's phone number.

The package is due to be on sale in April, covering all of the UK's National Parks. We'll have a review as soon as we can...