Is blackjack supposed to use multiple decks of cards to play?

Playing it on my iPhone and saw the same cards show up more than once just for one hand? Like saw the Queen of spades show up 3 times? Is that normal?

Based on what i've seen in hollywood movies, that's how they do it in the casinos. It's to making counting the cards harder or something

Casinos often use multiple decks, it doesn't change the way the game is played.

Yes. They use multiple decks to help prevent 'card counters' from getting an upper hand in the odds. The decks are also reshuffled before the whole stack is played out for the same reason. Since the rules for the dealer are set, knowing when there are more face cards left in the deck can let a skilled card counter beat the house odds and is considered cheating.