With the Modern Windows 8 UI, you can have utmost two apps showing on the screen at a time. However, you have to select a primary app, which occupies the majority of the screen space. The other App occupies less than 30% of the screen space. You can toggle between the views to change the sharing of screen space between these Apps.
However, there are many scenarios where one wishes to have two Apps open on the screen with each occupying half the screen. An example could be watching a lecture and taking notes at the same time. This is currently not possible in the Metro mode and I cannot understand why (I certainly do not see any technical difficulty in its implementation).
Is there a way to achieve this (without going to the Desktop view)? And if not, any clue why this is not supported?
Best Answer
There's no way to do this. You can only snap an app to either side of the screen and make it 320px wide or the remaining width of the screen. You cannot make them 50% the width, it's not possible.
Microsoft has a good reason for this: so that app developer can focus on what to show when you snap the app to the side. Remember that this is not the same as snapping in the desktop environment, when you snap a Modern UI app to the side, its content has to change as well to match that position. Allowing freedom to choose percentage of the screen to snap the app would make it harder for app developer to code their content accordingly