To make the Chrome Apps edit-reload cycle faster (especially when there's a build/compilation step), a helper extension could be written. It could reload the app using the management API. More importantly, it could have a custom hook to trigger the re-build/compile step before reloading the app. This could be as simple as an HTTP request to a local server, or something fancier with native messaging once that's available. This could all be triggered via a keyboard command using the commands API.
Chrome Extension Reloader Macro is something along these lines, albeit targeted at extension developers. LiveReload could also be extended to support this use case.