I am truly excited about the ability to easily extend Excel with “Office Apps”. I couldn’t resist checking out this new feature to create an interactive, drillable treemap/heatmap data visualization for Excel 2013. I am still tweaking it to read dynamic ranges of Excel data but the above was created in a mere couple hours with a web browser (no Visual Studio needed), my old JavaScript skills and some open source snippets from the D3.js or JavaScript InfoVis Toolkit. Just imagine the cool data visualziations you can use in Excel now! You are no longer limited with the out of the box charts…and you can bet that there will be a thousands of developers vying for fame and fortune publishing their apps to the Office App store. Sure you might have been able to jump hoops to create an add-in like this before…now it is so much easier.

What exactly is an Office App? Basically Office Apps can be developed using standard web technologies like HTML5, XML, CSS, JavaScript, and REST APIs. At a fundamental level, an Office App is an iframe type webpage that is hosted inside an Office client application that has APIs to read/write data and interact with the Office client application features. These apps can run in desktop clients or O365 Office Web Apps, and best of all also they work in mobile browsers – including Windows, iPad, iPod and Androids.. You could think of Office Apps a little bit like old VBA but a bit more robust, cloud and mobile friendly with a global reaching “app store” distribution system cooked right into the Office UI to easily find and add public Office Apps or private Office Apps that may be published for internal use.

To try out some of the public apps for Excel or build one yourself. Note that it is absolutely addicting when you see it all working together and a lot of fun. Finally I can break out the box and truly go nuts with any data visualization I want without excessive barriers and pain!

If you want to build one for yourself, this is where I started: http://msdn.microsoft.com/en-us/library/jj220082(v=office.15).aspx and http://msdn.microsoft.com/en-us/library/jj220065(v=office.15).aspx. You will need a free O365 Developer account that you can get here: http://msdn.microsoft.com/en-us/library/fp161507(v=office.15).aspx and Office 2013 Public Preview.