When installing an application, the App Manager console (or whatever how we call this), show "Installing the NAME_OF_THE_APP app" message, and it's usually quick. When you do this with a larger application (I tried with 13 mb one), it takes a lot longer to install the application on a real device (even on the simulator), so we are not sure if the process failed or if it's still installing the application. I would suggest adding a visual enhancement to show it's still installing. I personally thought the App Manager failed a couple of time with my device before trying it on the simulator. Since I saw it was working, I gave it more time, and it worked on the device too. Maybe it's a first world problem as we are used to having thing done right now/quick, but it's a small enhancement to avoid this issue.

I don't think it's a duplicate: my point is not to improve the speed (even if it's a good thing to do), but to enhance the UI experience when it's slow. Even if we speed up the process, it may be slower for bigger application, so we still need a UI indicator the application is still installing.

I agree.

This is more correctly a duplicate of bug 972069, which is indeed about the UI.