In reply to Lizzie:
From a technical standpoint it would be incredibly difficult to actually track climbing as opposed to running/cycling as they can use GPS and therefore get a pretty accurate estimate how far you have moved and what speed. For climbing I guess you would need a mega sensitive altimeter which isn't viable, and in case, 100m of VDIFF is not the same energy expenditure as 100m of 9a.
So really your only bet is a rudimentary estimate of calories burned which can be attained (inaccurately) from a heart rate monitor like one of those fancy fitbit things you put on your wrist. I think the expensive one has a altimeter in it as well, but more aimed at logging when runners run up hills.
I'd be interested to know how much calories climbing actually burns.
Post edited at 15:01