I agree with everyone who said it's not okay to ask. I think it's lovely if you enjoyed the gift and want to share what you ate at the restaurant, how you used the spa gift card, etc., but for the giver to ask just puts the recipient on the spot, and it implies some obligation to use the gift "properly" (by a certain time, for a certain thing, for yourself even if you don't like it, etc.) which is awkward all around.