In Universal Control, is there any way to switch focus from macOS to the iPad with a keystroke, rather than having to push through with the mouse?

In Universal Control, in order to start writing on my iPad, I have to switch focus by selecting something with the mouse, then the keyboard keystrokes will be sent to the iPad. In order to switch back, I have to reach for the mouse again. Is there any way to switch focus back and forth with the keyboard alone? An option that includes the apps running on my iPad in the Cmd + Tab app selector would also work great, maybe a custom app switcher does that?