What grid to use for mobile design?
One of the most convenient grids for mobile interfaces, similar to the web, is a 12 column grid. This grid will allow you to place both an even and an odd number of elements in a row.
How many columns are in a tablet layout?
Traditionally in a design system, the column width doesn't change but the number of columns change from 12 on desktop, to 8 on tablet, and to 4 on mobile. You can literally use anything you want, but most grids have 60–80px column widths.