Use someone else's mobile phone to transfer 100 yuan to yourself, Zhihu. Is it illegal?

Transferring money without other people's knowledge is theft. According to Article 49 of the Law on Public Security Administration Punishment: Anyone who steals, swindles, robs, robs, extorts or intentionally damages public or private property shall be detained for more than five days and less than ten days, and may also be fined less than 500 yuan; If the circumstances are serious, he shall be detained for more than 10 and less than 15, and may also be fined less than 1000 yuan.