Andy from the http://www.mountainsafety.co.uk/ website asked me to jot down a few words for the site about the benefits of tracking your hikes, so here goes (This post can also be seen at http://www.mountainsafety.co.uk/Nav-GPS-Tracking.aspx)...
GPS Tracking
With easily available, non-costly, current technology it is possible to use GPS data to track your hikes and share your track with others, both live and after you have finished. There are a variety of methods but here, I will outline those that I use.
Using Viewranger mapping software (an excellent way of using digital Ordnance Survey maps whilst out in the hills) on a smartphone, you can set it to record a track of where you have walked. Once in record mode, a line is recorded on your digital map showing fairly accurately where you have been, including time, speed and height data. When you finish, you are left with a detailed 'track' of where you have been. This can by uploaded to the Viewranger website and shared with people that way, but my preference is to export the track in .gpx format and save it separately on my phone.
Using file manager software (I use ES File Explorer on my Android handset) it is then possible to upload the .gpx file to track sharing services. Popular sports tracker websites like Endomondo can handle this, but my favourite for sharing your adventure is Social Hiking (+Social Hiking - Share Your Adventure on Google+). An uploaded track adds fine detail to a tracked hike and more accurately locates any linked media on the underlying map.
Once uploaded to your preferred sharing site, the .gpx file can be deleted. Or if you're like me, you can archive it for potential use. I currently save them in Dropbox but you can use any of the cloud servers or just leave it on the drive of your device.
What I have mentioned above relates to tracking and sharing your hike after your have finished. You can also share your location and live track whilst you're out and about. Again, there are a number of ways of doing this. I shall tell you how I do it.
Sharing your track live
Software like Viewranger has the facility to send live location updates. Viewranger 'beacons' can be set to upload to their server at various intervals. These can be viewed live by other people through their 'buddybeacon' feature, but I prefer to use Social Hiking to share my location and track. You can set up your account on Social Hiking to obtain your live location from Viewranger. The beauty of doing this is that people can see where you are at the time (there is a small delay so your reported location may not be exact) and interact with you via social media as you progress.
Unfortunately, it's not possible to live track using Viewranger when you're out of mobile phone coverage (although beacons that couldn't be sent can be saved and sent later when you are in coverage). If you're off in the wilds then a satellite device such as a SPOT is required to send your location. I have a SPOT Connect which sends a location beacon every 10 minutes via the satellite network. Social Hiking can then pick those beacons up from the SPOT Adventures website and share my location and track wherever I am. SPOT also has an 'SOS' emergency button that can be used to summon assistance should the worst happen.