I am still not sure what problem this is trying to solve. I can imagine that for beginners, not having to set up a development environment is an advantage of a web app.<p>But setting up JDK and IntelliJ|Eclipse|NetBeans typically takes five or ten minutes. After that you can use your environment everywhere and have a native experience (as far as native is possible using Java ;)).<p>It will be fast with or without internet, it will continue to work as-is when the company creating the IDE goes under or decides to double prices, I can use it with local tools (Git, Mercurial, JVisualVM), and my secret sauce does not end up on somebody else&#x27;s server.