Cloud IDE and XML editor

I need your suggestions for my project development for:
1. Cloud IDE, basically and IDE software which is available online on the cloud. Preferably FREE :-)
2. XML editor, a light weight software to edit XML files very easily.

Thanks in advance

One recommendation from me: CODIO
It is FREE for Public & Open Source Projects
Client Side: Perfect for client-side development with HTML5, CSS & Javascript. Sass, SCSS, Less & CoffeeScript also included.
ServerSide: Every project gets its own Box: an instantly available server-side development environment with full terminal access.

There are several ways to start off with codio
- Create a blank project (HTML Boilerplate, PHP Basic or completely empty)
- Import from a ZIP file
- Import from FTP/SFTP
- Import from Git/Mercurial
- A SalesForce project

Official documentation: https://codio.com/s/docs/getting-started/

Codio supports almost any programming language, and finally you can run it on your browser!