● Sometimes you have a negative review or two. Features were not in place or in-app purchases were not easy, ads were too long and game sessions were too short, who knows. You have fixed these problems and even commented on the feedbacks. But do you want new clients to consider whether to download or not reading these comments? No, you do not. So you buy app reviews with a positive experience.
● You have competitors that do not like that you are at the top of Google Play or App Store search. They order negative reviews for your product and newcomers do not trust your application. You can write under each review but it will not save the situation anyway. It is better to add more positive reviews to your application and push those negative down the list.
● You want to improve the overall rating of your app. Many devs (more than 70% so far) target 4+ rates, so they try to add positive reviews and ratings to their app on a regular basis.
● Finally, it is brand, trust, and explaining what your app is about. What to convince that your app gives what the user was searching for? Write it in your reviews for him/her. Let them be sure they know what they download.