There are two ways to hide the “Recording” notification icon on the notification bar on top of the screen.

Firstly, you can enable “alternate icon” from app Settings > Interface. This will replace the circular recording icon with a more obscure diamond icon.

Secondly, you can completely hide the icon from the notification bar, by going to app Settings > Interface > Hide notification icon. This will hide the icon that appears on the top-left corner of your screen, but when you pull down the notification bar, the entry that says that recording is in progress will still be there. This is a requirement mandated by Android that a background-running app must have a visible notification in order for that app not to be terminated prematurely by the operating system.