For App platform, App Install & Uninstall is the key acquistion & product metrics. If a company publish new version, the existing & new users installs the New version of the App. Most of the companies come up with different strategies to maximize the install & retain the existing App Consumers.
The Existing Install & Uninstall Concept is painpoint for business & consumers because, every new version is realised the consumer needs to be update / install the App.
In Future, I personally feel that there is no concept of Install / Uninstall. The App can be accessed from cloud. Just register / login from the cloud.