Go here for more on the technology and development of the GPS watch.
Running
Garmin Forerunner 205
A good example of a GPS running watch would be one made by Garmin. Garmin makes six watches aimed at the runner, depending on how many or which particular features you need. At the entry-level you have the Forerunner 205 which is a good choice for runners who are looking for a good way to get basic GPS location and performance data.
According to Garmin, the forerunner 205 sports a unique design that houses a high sensitivity GPS receiver in the watch strap. This is intended to help with tracking capabilities during heavy tree cover or near high buildings as well as more accurate readouts for speed and distance. The curved design of the watches body means that the antenna points to the sky when you are running, helping with reception as well as helping with viewing the display.
Although you cant use the Forerunner 205 for sophisticated navigational purposes it does come with some standard features such as basic mapping and routing capabilities and also waypoint marking. Furthermore there are also features such as the “go to location” that can take you back to your original starting point or any location that you enter. If you enter multiple locations you can choose to define this as a route which can be used over and over. There is also a feature that lets you zoom into a basic map displaying your current path and direction.
The watch can be charged using the same usb cable used for data transfer from the pc.
Price:$130
Link: Garmin
Cycling
All the major GPS watch manufacturers either make watches with specific cycling related functions or offer accessories.
The Polar RS800cx Pro Team Edition is a GPS watch specifically aimed at the cyclist and it comes with both cadence and speed sensors.
Features:
You can define profiles for up to two to three different bikes and select the appropriate one for your training session.
Cadence
This is the pedaling rate in revolutions per minute. Cadence is critical in enhancing a cyclist performance, an increased cadence means less down force required when pedaling. Furthermore alarms can be set that are triggered for different cadence zones to aid performance improvement, these can be visible or audible or both. These types of alarm settings are also available to be set for heart rate, speed and power output, with both upper and lower limits so that you can adjust the intensity of your workout.
Speed Alarms can be set that are triggered for different upper and lower speed zones to help by basing your training session on speed.
Distance Various readouts in kilometers and miles including the distance travelled in one training session and the distance of one lap.
Incline Shows you in grades and percentages the uphill or downhill of the incline helping you adjust adjust your effort accordingly.
Price:$450
Link: Polar
They also manufacture a separate Polar Cadence Sensor W.I.N.D for mounting on the bikes frame as well as three cycling computers the CS600X, CS500 and CS400.
Garmin: If you want a gps watch to double as a cycling GPS watch then one option to consider would be the Garmin Forerunner 301 which comes with an optional mounting kit for the bike. They also make three cycling computers, the Edge 500, 605 and 705
Suunto: If you have a GPS watch or are a cycling enthusiast and intend to buy one, Suunto make a couple of handlebar adapters, one that works with oversize handlebars too. They also do a “cycling pack” http://www.suuntowatches.com/Suunto-Cycling-Pack.pro
Military
The Suunto X10 Military.
Whilst the X10M is aimed at Military personel the standard X10 has almost the same features, the main difference being that the military version gives you a choice of compass measurements between Mils and Degrees and comes with a red backlight.
The X10 has the fastest GPS capabilities of all the Suunto GPS watches, so that tracking is available even during severe storms or thick jungles.
Features the capability to plan your routes on your PC and then upload them to the watch. It is compatible with National Geographic TOPO! Maps, Google earth and Fugawi. You can record your path as an aid to finding your way home, or simply back to your car. Also if you happen to find a specific location that you would like to return to, you can save those coordinates. To further help with route planning it comes with Suunto Track Exporter PC software.
More specialised features include an Altimeter, this can be useful for not only military use but also mountaineering, backcountry skiing, and wilderness travel. It not only displays your current altitude but also the rate of descent or ascent. Because the X10 GPS watch captures all the altitude information and saves it to a logbook it makes it easy to analyze your performance and develop your training regime.
The Altimeter can also be useful for pinpointing your location on a topographical map by using your altitude when you are located on a promontory or near a large body of water for example. Likewise if you intend to hike to a certain peak in order to traverse across a ridge then the altimeter will in this regard. It is accurate from 1,600 to 29,500 feet.
In order to help to predict inclement weather conditions a barometer feature is also included which uses atmospheric pressure to measure the conditions.
As well as typical GPS watch readouts of speed, distance and direction, it has a calendar, an alarm, dual time, is water-resistant to 100m and comes with a long life battery and usb charger.
Suunto also recommends the X10 for “geocaching”, which is “a high-tech treasure hunting game played throughout the world by adventure seekers equipped with GPS devices. The basic idea is to locate hidden containers, called geocaches, outdoors and then share your experiences online.” to quote geocaching.com
There have been reports of problems with the buttons and faceplate coming unglued with this watch so that is something to consider.
Price: Military version:$500 standard X10: $390
Link: Suunto
The only other option for a Military GPS watch would be the MTM OPS GPS Navigator watch (price $490) Link