This isn't restricted just to hand-helds, either.
The Garmin 430 in my aircraft (well, it was in my aircraft until it broke and we sent it back for repair) doesn't know what way it's pointing when it's stationary, and that's most definitely not a hand-held. But as soon as you add power and start to taxi, it figures it out (and orientates the map properly if you've selected track-up).
FFF
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