Established by whom? Many people host their apps on Google Play just so they don't subject their users to warnings about "installing apps from unknown sources" and for convenient updating.
> user engagement and revenue stream
Well, if you're making an app for the sole purpose of making charts go up...
A sizeable portion of Android users are not technology savvy, the "installing apps from unknown sources" message will deter some of them.
>Well, if you're making an app for the sole purpose of making charts go up...
Unless the app is a hobby project, most people would put maximizing their potential revenue stream and marketability of their product as a high priority.
> user engagement and revenue stream
Well, if you're making an app for the sole purpose of making charts go up...