Recently, the Google added a new function - you are be allowed to try the app before you install it. It is a good function for users to learn about an app clearly. Also, it can build a good user experience to increase the conversion rate of an app. Therefore, according to this new challenge, app developers have to focus on the app quality. If the quality is low, your app will get a few downloads.
Although the new change, the app installs, reviews and ratings are also have a huge impact on app ranking. Also, the users would like to try an app that has more downloads and positive reviews. In the new competition, you have to try your best to get more installs and reviews to attract more users. If you have enough budget, you can buy app reviews and installs to achieve your goal!
Good luck! Angel