I have a Nexus 4 with Ubuntu Touch. It is now updated to OTA12.
I wonder, because if I connect the device via a Slimportad adapter to my external screen, it does not switch into convergence mode. The screen of the Nexus 4 can be used as keyboard and mouse touch pad. And at the big screen I can see the mousepointer and the normal screen layout as I am used to see on the screen of my Nexus 4.
I remember at OTA10, Ubuntu Touch switched on the desktop mode automatically, if conected to an external screen. In desktop mode I should see normally windows with titlebar and all all apps are running at the same time.
I know some Aquaris devices do have an build in switch at the System-Notification-Tab. But at the Nexus 4 there is not such a switch.
I even did a full reset of Ubuntu Touch. But this did not solve the problem.
How do I switch into desktop mode?
One possibility is to install the "UT Tweak Tool" from the "OpenStore" and select in the "Usage Mode" Tab "Windowed". Then you have a windowed user interface. That's not a nice solution because it should switch automatically, but the tool also offers cool other features.
Also, from the terminal:
To go back:
I had some emails with the Ubuntu Phone Team: MailingList
Pat McGowan did an awesome prescription about how Ubuntu Touch handles the Desktop Mode. Here is an excerpt of his answer:
"The latest logic switches to Windowed mode when a mouse or touchpad is available (not based on having an external monitor), so your Nexus 4 should switch because its acting as the pointer. However it also checks that the width of the screen is at least 60 grid units, which in this case is only 1080 pixels. I believe there is similar logic to decide whether to display the Desktop mode toggle in the session indicator based on screen width."
My problem was, that the resolution of the external screen was not detected properly.
I filed now a bug to improve the user experience regarding the possibilities to use the desktop mode. The Link goes here. Every one who likes my proposal is welcome to click to "This bug affects you" to add more bug heat.