Can you use Qt for mobile?

Android does not support PyQt4. However PyQt5 supported (see this). However, you could port your application to use PySide. It provides bindings for the Qt4 platform.

Qt is the solution that lets you connect the dots across platforms and between online and physical experience. Deploy your apps on Android, iOS and Universal Windows Platform (UWP) .

On the desktop, PyQt is better because you can get a near-native look and feel easy and you have a simple gui designer. But on mobile, it makes more sense to go with Kivy. Kivy is more oriented towards mobile interfaces. PyQt is more oriented towards desktop software.