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That's debatable. You can try drying it out for a few days and then try turning it on. In the meantime I would definitely turn it off and keep it off. Time is the only thing that will tell unless it has already starting showing signs of damage. In the end though, it may stay working or could start showing water damage anywhere down the road. Be prepared to have to replace it. Wish I could have offered better news, but water or dropping an iPhone are probably some the worst things that could happen to an iPhone.