[elwynw]

I wanted to know, if I've pushed an app to users, then delete the app from the server, and perform a loader /reindex, will it remove the app from devices?

[ashworth]

The application will not get removed from the user. the only way it will get removed is the following.

the Admin sets the dispostion to disallowed.
the dispostion is set to optional and the user deletes the app from the hh.
the hh dies