Dont rely on the compass too much but its a handy backup - the barometer is useful for weather (what its intended for I suppose!) - lying in your tent listening to the wind and rain you can at least get an idea of which way the weather is heading. The history function is particularly handy for this, as well as the trend lines on the main watch face, just dont forget that any ascent/descent you do will affect these readings - best checked in the morning if you have been stationary at one point overnight, or at least at the same altitude all day.