Material 3 Expressive Theming & Full Tablet Support with v4

Is your feature request related to a problem? Please describe.

Yes. The current experience could be improved with better support for Material 3 Expressive theming and tablet layouts. On tablets, especially in landscape orientation, the UI can feel awkward because there is unused space on both sides, with black bars appearing around the content instead of making better use of the available screen width.

Describe the solution you'd like

I’d like to request:

• Material 3 Expressive theming support in v4, including the updated expressive components, shapes, colors, typography, and motion where appropriate.
• Proper tablet support, with a responsive/adaptive layout that takes advantage of larger screens.
• Improved tablet landscape support, so the interface scales and reflows naturally instead of showing large black areas on both sides.
• Ideally, the v4 UI should follow modern Android adaptive-layout guidelines and provide an experience that feels native on both phones and tablets.

Describe alternatives you've considered

Using the existing phone-oriented layout on tablets is an option, but it leaves significant unused space, particularly in landscape mode. A responsive/adaptive layout would provide a much better experience.

Additional context

The main issue is noticeable on a tablet in landscape orientation, where the content is centered with black bars on both the left and right sides. It would be great if v4 could use the full available display area and adapt the layout specifically for larger screens.

Overall, I’d love to see Material 3 Expressive + proper adaptive tablet support as part of v4.

Start by locating the Android v4 UI, theme, and tablet-layout entry points; the issue names no files or tests. Compare the current phone and tablet landscape behavior with Material 3 adaptive-layout guidance. Done means expressive theming is implemented where appropriate and the interface uses the available tablet width without black side bars.