This Windows 8 app is available for some time now. This app makes it possible to create powerful Business apps and publish it without writing one line of code. More information can be found on Microsoft Project Siena site. It sounds great. Business users who click their own apps together to simply their own work.
Sounds very interesting so I wanted to try it myself. After starting the app, you will the screen below. An empty screen on which you can add Visuals. It is recommended to look at some of the tutorials. Personally I found the flow, workflow or the way the app work not very intuitive. Well, we start with a empty window.
Business apps are interesting if they show data. Data comes from a Data Source. By a right click or swipe down you get the meny on top. In this menu the standard file functionalities, adding data and adding new screens. On the right there is a Preview button.
With App data you can those from multiple standard data sources. For some connections you need a developers account or connection data. For example Yammer, FaceBook, Twitter etc. In my example I use a RSS feed.
After clicking on Import data, Siena tells you the data source was connected.
There is also an example of the data the source provides. You need more data sources? Just add more sources.
On the windows we need something to show the data. To do that click on the Plus sign at the right side. There is a list of many possible controls. For my demo I choose from the Galleries the Text Gallery. This contains a combination of fields etc, which limits my work for design 
At the bottom a menu pops up, you can choose the wanted data source. For my App the data source is RSS_1. On the window the data changes to the data from the source. The default does not show the correct data as I would like it. The first row shows the tags of a Blog item etc.
This can be changed very easy. You select the field and choose from the menu below Text. There a list of all available fields form the data source. Just check the correct field.
Done this for all the fields. I also added a picture of my Gamestag and some text. To run the app choose Preview from the meny at the top.
Your app will show. Which look in my case like..
Super easy. If your app needs more page, just add more windows. In your windows you can add navigation. How to add parameters is not clear to me yet..
Resume: I think this is a great start. Although there schould be done to the user interfacee, but it is a start. In the keynote of Microsoft Partner Conference there was a demo of the next version. I also hope there comes some possibilities for security or possibilities for Enterprises to add their own data sources. Those Enterprises want to expose their ERP systems or other internal data sources but keep it secure and controlled. Business users making their own apps is not strange, but it should be a little controled. By the way 15 years ago Excel and Microsoft Access were used by Business users a lot and it went out of control in some Enterprises.
I am curious for the next version and which data sources are added. Keep you posted!