In the ‘good old days’ (last year) apps were only open or closed. Yes, those were simpler times.

Nowadays apps can be open, closed, dormant and all sorts of states in between. When it comes to user experience it’s our job to understand how an app behaves in various states of open-ness, and how the user experience transfers between those states.

Between Closed and Open

By “half-open apps” I’m referring to apps that provide some “intermediate” states that are open, but not quite “fully open”. Let’s say that a “fully open” app is one that is providing access to all its functionality, using it’s “full” user interface (on a mobile platform that typically means “full screen”). An example of a “half-open” app might be a desktop widget that provides a limited “window” into the full application.

When an app posts a toast notification, or updates a live tile in Metro, we could say it is “a little bit” open. When an app is snapped to the side in Windows 8 we might say it is “mostly open”. An app might be fully opened when it is “full screen”.

Half-open Metro Apps

When we look at Microsoft’s Metro apps for Windows Phone and Windows 8, what we actually see is a continuum from closed to open. For Windows 8 Metro and desktop apps we see the following:

	NOT VERY OPEN
“Toast” Notification		Metro
Start Tile (both sides)		Metro
Snapped app		Metro
Open app		Metro
Desktop app	Office 15 Technical Preview – Metro Style from The Verge	Windows Desktop
	FULLY OPEN

Continuum between Metro apps and Desktop apps

I include Windows Desktop apps in the continuum because I predict there will be many Windows 8 Metro apps which will provide continuity with a “Full Service” traditional desktop application. For example, It would make sense for a Metro Photoshop app and a Desktop Photoshop to interact, presumably via “the cloud”. Many line of business apps will follow a similar approach: they will provide a predominantly “browse-y” experience in Metro (think dashboard), while requiring users to “drill” into a full desktop app to do intense transactional work.

(The reason for this could be simply to access the greater power and flexibility available on the Windows Desktop, or it might be to access the more powerful User Interface paradigms of the desktop. Don’t make the mistake of thinking that Metro has made the traditional Windows Graphical User Interface irrelevant.)

User Experience Design: Always Open

These days we talk a lot about designing services that follow people across different platforms (smart phone, web, call centre etc.) Particularly with Metro (but also with things like Android widgets) we also need to start thinking about designing services which follow people up and down the various states of “open-ness” within each platform.

So of course, when I say “app” above, I really mean “service”. A seamless service might well actually be delivered by several applications. The important thing is that people are not tripped up, or confused, by the transition between them.