A SPA app can have multiple pages and/or tabs: think Google Docs or Google Spreadsheet. The difference between a SPA app and a web page is that the app "page" never changes; just the parts inside, as if it were an application on a desktop. A SPA app typically sends html and some organizing javascript to the client, and then content drives the rest, using the organizing javascript manage the display of the content, in tabs, which effectively are like separate pages; fly-ins; modal dialogs; etc. One of the big advantages of a SPA app is that content is separated from the app. Another is that offline work becomes possible, provided you've got a way to store the needed content locally and a way to update the backend when reconnected -- and that's getting easier to do. Having been to the SPA session at SWFox, it is clear that SPA apps are not trivial to construct.

Hank

PS: while this is irrelevant to .Net development, it's worth noting that Lianja creates the SPA app for you, using all the same javascript technologies you might use to do this, but without your having to roll-your-own-framework. If you can find a framework that does that for you in .Net (I haven't looked), it would likely be worth investigating.

>I have a question about the following design approach for web application which targets are tablet browsers like iPad, Nexus, etc. The approach I choose is the following:
>The main page of the application has a pull-down menu. When user clicks on an item of the menu a new tab is opened. For example, one of the items on the menu is View Order. And I envision that a user may want to see several orders at the same time. So when he/she clicks on this menu anchor, a new tab is opened where user enters order number and views the order. At the same time he/she can click on the same menu item again and open another tab to view another order. And so on. So practically, the main tab/page of the application will host the main menu and some static text (I have not come up with what text though).
>What do you think about this UI approach? Would this type of app be called MPA (Multiple Page Application) as opposed to SPA (Single Page Application)?