I'd say the most practical application of a digital compass (really a misnomer, electronic compass with digital display would be more appropos) is when it included as part of a GPS system. Otherwise, why have yet another survival tool that must use batteries, and will eventually fail, when something completely passive and much more rugged will do just as well or better? As for memory, I would have higher confidence in a piece of paper and pen than another electronic memory device that will also fail eventually, maybe at the worst possible time.
This is my caveat: Do not rely too heavily on electronic devices, they require something you cannot always provide, a power source. Whenever possible, stick with what you know works and use the electronics as a convenience and not a necessity. Going into a cave with nothing but battery powered light sources will make you a believer.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)