In the age of technology, the smartphone is a useful and necessary tool for human life. However, in addition to the undeniable benefits, we should also be cautious with the negative and the risks that come from the smartphone. The negative aspects of the smartphone are likely to appear largely due to the carelessness of users. There are many subjective people in the disclosure and sharing of personal information widely. This contributes to the attack and illegal exploitation of information of cybercriminals. We should only be friends with people we really know in real life, and keeping up with our status as well as our location is also not recommended. Also, the smartphone has real effects if we spend too much time on it. Many people are willing to give up work, friends and even family because of the smartphone addiction, and now there are many cases where medical and psychological interventions are needed to get some people out of that kind of addiction. The strong development of social networking also makes our real-life relationships more difficult to maintain, and many people are not even able to communicate well with friends in person. Sitting too long in front of a computer screen or phone also causes physical injuries and a bad influence on our eyes, neck or spine. the smartphone is not bad, and most of the negative things are caused by the neglect of users. We should consider the smartphone as a useful tool, not a thing that can control us.