The cold temperature itself has no effect on electronics. However the moisture in the air freezes and attaches to the electronics as frost. If you try to turn them on immediately, the frost would melt and it would be like dipping the equipment into the bathtub. If you leave electronic gear out in the cold I suggest you bring them inside into room temperature and leave them 24 hours before trying to power them on. 

I wouldn't leave any tablet, smartphone, laptop, or any other electronic gear in the car when the weather dips below 32 F.

Your in-dash electronics, on the other hand, is air-tight and moisture-proof so the cold does not effect those electronics.