I use code-server[0] to access VSCode on my iPad in Safari, and it works pretty well. There are some rough edges, but (aside from the better shortcut integration and UI polish) I don't think a native app is going to provide a lot benefit because I can't execute arbitrary code on the iPad anyway. You're going to end up with a mostly remote experience either way.
[0]: https://github.com/cdr/code-server