I've seen Las Vegas casinos in movies and kept wanting to go there. But I also know that there is also an online casino that is always with you on your phone. Is there a tangible difference?

As far as I am concerned, the difference lies in the stakes - in Las Vegas they are definitely higher, and you still have to fly there and book a hotel room, which is not always easy. And live emotions from winning can be experienced in online casinos, for example in https://treasureisland.games/ . You will also feel like a treasure hunter, which you are unlikely to experience in Las Vegas.