Can a friend who steals a friend's mobile phone be dismissed after filing a case at the police station?

This should be theft. Theft is a public prosecution case, but it doesn't mean that the victim will be finished by dropping the lawsuit. Under normal circumstances, the procedures that have been started will continue. Because the object of theft not only violates the victim's property rights, but also violates social security, which belongs to the crime of public prosecution.

In this case, it is generally impossible for your friend to get away with it, unless you can find strong evidence to prove that you are a friend-like accomplice, with minimal subjective malignancy, and voluntarily surrender afterwards, deeply realize your behavior mistakes, actively repent, and obtain the understanding of the victim. On weekdays, your friend behaves well, and then find a bunch of people to prove that this is a good boy, only occasionally slipping. The best result of the work done by the procuratorate is not to prosecute.