Stop worrying, it won't fix anything. If it was a gift, it was a gift. A person who wants to sue must generally pay a filing fee to sue in small claims court. Then the person must prove his claim by admissible evidence. Assuming the phone cost what phones cost, I can't imagine it would be worth his while to pay the filing fee; but even if it was, he's got proof problems. And he hasn't done any of what you are worried about. So, stop worrying.
Not legal advice, just my two cents. I don't practice law in Pennsylvania or hold licensure there. If you need legal advice, consult a lawyer who does.