When you remove an app, it is only removed from that specific device. So it's entirely possible to get out of sync if there were to be some sort of home screen synchronization of apps. Usually on each Roku I just put my most used in the top 6 and bottom 3 so I can just scroll either direction to get what I'm after fastest.
When you remove an app, it is only removed from that specific device.
??? When you remove an app, it is removed from your ACCOUNT, and applies to all devices. I wondered if this happens instantaneously or just the next time the device updates, so I tested by removing a little used channel from one of my devices -- it was gone from the other one by the time I walked one room down the hall to view the other set.