The block

Choose a unit in the row above the block and tap the grid, or drag it in. R turns clockwise, Shift+R counter-clockwise, and M mirrors, even before you place it. If the preview turns red, you replace the units that are there. Tap a unit in the block to select it: then you turn, mirror, move (arrow keys) and delete (Delete) it.

By default you only see the units of one cell and the ones the project uses; the rest are under "+ more". With "Customise units" you hide the ones you do not use and make your own in another size, such as a square that fills the whole block.

Tap a number in the palette, then tap the pieces in the block to give them the fabric. With Shift you paint the same piece in all matching units at once. Esc or "Done" ends painting.

Tap the block's size in the bar over the block ("7 × 7 cells · finished …"): there you choose the grid and the cells' size, and the block's finished and cut sizes are shown under them. "+" and "−" on each side of the block give it more or fewer cells there; "−" first shows in red what goes. The ruler along the block shows the cells' and the block's sizes.

A project can have several blocks. Press "New block" above the block for an empty block or a classic block from the patterns, drawn in your fabrics. The blocks can each have their own size; if a block does not fill its place in the quilt, QuiltCrafter says so and offers to give it the right size.

The bar at the bottom, under the block and the quilt, decides how the whole project is shown: numbers, seam lines (the arrow beside them picks their colour), the ruler, fabric print or flat colours, and the quilting. The numbers on the quilt are as large as the pieces have room for, so they can be read on paper too.

On the right of the bar you zoom with the slider (or Ctrl and the wheel, or two fingers); "Fit" shows it all again. Full screen gives more room, and Esc leaves it. On a narrow screen the view is gathered in one button, "View".

"Notes" at the far left of the bar are your own notes, on the block in the block view and on the quilt in the quilt view: e.g. where the fabrics were bought, or what to remember when you sew. A dot on the button says there are notes.