Once this daemon is running, Parallels Desktop doesn't need to be open, so you can run a VM without having to keep the application launched. If Parallels is open, it runs in a visible window. If Parallels is closed, the VM runs in headless mode where the only way you can tell that the VM is doing anything is by looking at the host machine's CPU usage

When you're using a VM on the iPad, you see the compression updating repeatedly even though the screen isn't changing, so it's not a particularly efficient remote client app. As a VNC client, it's not as good or as fast as as iTeleport for the iPad.