Prevalence of smartphones is growing among children. It presents threats to children. Children’s unlimited access to smartphones may become study distraction. Even worse, children are at the risk of privacy disclosure when they are using smartphones. Therefore, parental control is necessary on smartphones. However, as the most popular mobile operating system, Android provides little parental control features. Existing parental control applications on Android are vulnerable and it is difficult to develop a good parental control application on Android. In this thesis, we study parental control issues on smartphones and propose Simple Parental Control(SPC) to address them on Android. SPC is fine-grained and context-based. According to our experiments, SPC introduces little power consumption and restricts applications’ access to specific resources without compromising other functionality.