how can I program life like random dice?

Id like to make a dice game but i have a few questions about the randomness for dice. If possible id like to use the same randomness that there is in the real world. the app will be for ios and I will be coding it in swift using some ar kits from apple. Id like to know if it would be better to make a algorithm for the roll or if I should let the user shake/roll a 3d dice the game(relying on physics laws for the roll). Which of these will replicate real world randomness?

Thakns!