ProjeQtOr is a Web application, that runs on client side with any browser.
So it is compatible with mobile devices.
But, as project management required many data, and so quite complex screens, it is not fluent to use on mobile device withouit an external keyboard. Virtual keybord will take half of available space on device screen, so forms will not be very fluent to use.
We are under progress of designing a specific mobile interface that will be provided as a plugin. But it will cover a much smaller perimeter of features than web-base one.