External keyboard required. Numbers keyboard shortcuts on iPhone only activate with a physical keyboard connected.
Command modifier. Numbers on iPhone uses Command (⌘), following iOS keyboard conventions.
Cell navigation. Moving between cells by arrow key and navigating within a table are available with an external keyboard.
Formula entry. Entering and confirming formulas with a keyboard is supported.
Discovering shortcuts. Holding Command on a connected keyboard in Numbers for iOS shows available shortcuts for the current context.