Though I always hear some experts say that less screen time and more free time is good for our health, nobody does it. In fact, more and more people don't know what they should do without their smart phones. So, we have to accept the fact that smart phones have been playing the most important role in our daily life. In that case, communication apps provide new ways for people to keep their interpersonal relationship which are really different the common ways. These social meidas make a new human race, they call them "I-Man".We do everything with different apps. They seldom meet people in person. So, we need to master the skills to use these apps. This is what the world requries us to do!