I don’t really have a must-have app on my phone. I am just forced to use a variety of apps on my phone. The store app offers different kinds of apps for different uses. Some people are keen on downloading a lot of apps and using them all day long. Among them, apps created for entertainment are really popular. These apps can analyze the dates of the videos, articles and pictures you have browsed and then suggest similar content to watch next. So, a lot of people, especially the young, are addicted to the "digital drug". For teenagers, their brain can be deeply changed by these continuous and irrelevant videos or articles that cause them to struggle to focus on their school work. Slowly, they get used to enjoying the short excitement the apps can give them. So, what app is a must-have depends on what it brings me.