I was really surprised that many of the web IDEs don't support the external keyboard in iOS.

I haven't tried repl.it, but the ace editor (which cloud9 uses) doesn't support the arrow keys on the external keyboard for iOS which is a deal breaker for me.[1]

Code Sandbox [2] however allows you to select which editor (Monaco or CodeMirror) and CodeMirror has a fix for handling the arrow keys. I've found Code Sandbox works pretty well on my iPad - it has a nice Github integration so I can commit directly or open pull requests from the web IDE.

[1]: https://github.com/ajaxorg/ace/pull/3172 [2]: https://codesandbox.io