I was in fact talking about an actual life raft on an actual boat, which had been fitted with an actual TomTom in case of its necessity it a survival-type situation. (I will assume it was a TomTom since they use cooler data, even though I do not know for certain in the context of this conversation.) However, it struck me that this could be extrapolated into a philosophical discussion of some sort.
It could even become a pithy saying of some sort eventually, like "A bird in the hand is worth two in the bush" or something. Except that the term GPS is not quite common enough yet, I think. I expect it will be with time. Just like people talk about googling something, it wouldn't surprise me to hear comments like, "I GPS'd my way there."