There are an amount of applications that we have installed in our mobile phones. But using every single application seems impossible, and we all have some all-time favorite app. I am going to share with you a useful app which is called Mobike. This is a bike-sharing application that is also an innovative transportation system. The company puts thousands of bikes in the streets, and you can use one that is available by paying deposit. So you? can ride a bike for 1rmb every 30 minutes, and you can even get a free ride. Before using this app, I didn't? ride a bike for almost 7 years. The reason was I didn't want to buy one, because my bicycle was stolen for three times. So I decided to walk rather than rode a bike even though I needed to walk for more than 30 minutes. Since I downloaded this the Mobike, it was such a life-changing experience for me.? I can only click the app and use the camera to scan the QR code on the bike to unlock it. After I use this app, I don't have to worry about the theft who will stole my bike. I think this app plays an important role in my life. Moreover, using this app to ride a bike helps me to save a lot of time. I also consider that riding a bicycle is a kind of exercise, and it can help us to live in a healthy lifestyle especially for people who have a sedentary job.