GPS navigation (Global Positioning System navigation) has become an everyday technology, with cars and even phones building it in for convenience. GPS is a US-government owned space-based radio-navigation system that is freely available worldwide. Small electronic devices can use the power of GPS to accurately locate where you are and guide you to where you want to go. More and more of us are now using GPS in our car everyday to find our way around.

GPS is also available in handheld devices. These can be invaluable for walkers by keeping them on the right route, pointing the way to interesting waypoints and allowing them to save their favourite routes for another day.

There are a range of easy-to-use devices available aimed at hill walkers, climbers and those walking to keep fit.

Garmin eTrex H
The Garmin eTrex H comes with a high-sensitivity GPS receiver that will quickly find satellite signals and promises to maintain accuracy even in tough conditions.

It has an intuitive interface and a rugged exterior, yet remains lightweight and fits in the palm of your hand. You can operate it with one hand using the five buttons within easy reach on the side of the device.

Importantly, the eTrex H is IPX7 waterproof. This means it will stand up to a sudden rain shower, an accidental splash or two or even a brief dip in the water and won't cease operating just when you need it most.

The eTrex H is WAAS (Wide Area Augmentation System) enabled. WAAS is a system of satellites and ground stations that can improve the strength of GPS signals by up to five times. Using WAAS means that the eTrex H can track your position even in heavy cover and deep valleys, and up to 500 waypoints can be stored in the device’s memory for easy retrieval.

The eTrex H is fairly simple to use: you enter the point you want to go to and the device will point the way. It has no street or terrain maps, however, so familiarising yourself with the conditions on the route is essential.

It has a useful TrackBack feature, which will reverse the track log and guide you back to your starting point.

There is one last important consideration: battery life. The eTrex H uses two AA batteries that provide up to 17 hours of power.

Mobile phone applications
If you don't want to invest in a dedicated device, you could turn to your mobile phone. GPS-enabled iPhone users have a simple option – download an application like MotionX-GPS Lite free from the iPhone App Store, and your iPhone becomes a navigation device. MotionX-GPS is designed for biking, running, hiking, walking, skiing and other outdoor sports. It includes terrain and street view maps, and users can also email their position and other information like the track, time and distance covered.

There are other GPS applications available on the App Store for a few euro each.

GPS can only be used on the iPhone 3G and the newest 3G S device, as earlier versions do not have the necessary technology.

Of course, using the GPS will decrease the iPhone’s battery faster than usual, so it might be an idea to have a second way of contacting people should anything untoward happen.

A word of warning: GPS devices are all well and good, once you know how to use them properly.