Losing the watch doesn't mean you are without a compass...unless you literally had a compass strapped to the band.

Knowing the time (from your cell phone), it is an easy matter to sketch the clock and determine North from there...
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Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein