Both, and all/any others. That’s because it’s not an “app”. It’s a “responsive design” web site that adapts to changing screen sizes (small, medium, large) in any modern browser.
To a limited extent that’s also built in to existing kiwitrees. But the current layout, with features like excessive use of tables, makes it impractical to progress further than I have.
Kiwitrees-nova uses the exact same under-lying code (the php), but every page will need its display structure (HTML and CSS) rewritten. So not a quick job ☹️