Everything around the world has both a positive and a negative side. If you ask me what I use most in my daily life, I’ll definitely tell you that it's the app called WeChat on my phone. I contact everyone via this app and I receive and send a lot of messages about work through it. The app sends me notifications to remind me to pay my bills and gives me the possibility to pay them as well, it's very convenient! After work, I always check WeChat whenever I hear the sound of a notification. When I have lunch or dinner with my friends, we often look down on our phones while quickly scanning the screen. In fact, we are just entertaining ourselves by watching livestreams or videos and most of us end up having terrible pain in our neck. The worst thing is that we have lost the ability of communicating with others. We don't know what we should say while talking with others in person. We get used to taking out our phone and doing something on it. So, if we call this is a must-have app, what is its purpose?

Everything around the world has two sides. One is positive, and the other is negative. *This isn't necessarily true. better 'There are two sides to every argument'. If you asked me what I use most in my daily life, I would definitely tell you that it's the app called WeChat on my phone. [conditional structure] I contact everyone via this app and receive and send a lot of messages about work through it too. I get notifications for all my bills on it, and pay them on the app, too, which is very convenient! *Link sentences then you can omit unneeded words. After work, I take my phone all the time and check WeChat whenever and wherever I hear a notification sound. When I have lunch or dinner with my friends, all of us look down at our phones, and scan the screens at a quick speed. In fact, we are just entertaining ourselves by watching livestreaming or videos. Most of us have a terrible pain in our necks. The worst thing is that we have lost the ability to communicate with others. We don't know what we should say while talking with others face to face. We get used to taking out our phones and do something on them. So, if we call this is a must-have app, what is your purpose? *Unclear end point.