Touchscreen-friendly Control Panel? Clicking and dragging Grid, Low Reorder entries, etc.

I’m currently building a site where my clients need to have full control of the CP while working in the field. This of course usually involves a smartphone or tablet and I’m not sure where I should even begin in terms of endeavouring to add touchscreen features to the CP. Maybe it already exists and I’m missing it.

Any thoughts or ideas as to where I should start would be greatly appreciated.

Thanks!