Welcome here T. B..
Altough this watch packs a bit more computing power than I´ d want on my wrist it may be a nice tool.
For the rough estimation of your position you also need the altitude of the sun to determine the distance. When you make two observation a least one hour appart and do some correction for the refraction the position could be in a 5 sm radius of the estimation. I tried that with a cheap cardboard sextant and it was better than that most of the time. When you search for protractor or sextant you may find some information about the additional tools and techniques involved.
The links should be OK as others post links too. After all we might wish to know where we could get that gear.