In Settings → Channels you can see the available names that can be assigned to the oscilloscope channels. Set a specific name for a channel is just a self reminder for the visualized data. No function is associated with the Channel naming.
If you don't use some channel name of them you clicking on the eye and hide it.
You can add or remove custom names with the + and - buttons. You can remove only custom names previously created.
When you modify this list HScope saves the current configuration in a file called
Channel_Names.cfg under your HScope document folder.
By clicking on the document icon with the + on you can import a custom names list from file (from example a configuration saved on another phone).