Tool options

Select a tool first. On desktop and laptop its settings appear in the options bar above the canvas. On a phone the same settings wrap below the tool rows and above the canvas.

Unless a shortcut is listed, a setting has no dedicated keyboard shortcut. On touch screens, tap buttons, checkboxes and lists, and drag sliders. Draw and Fill have a hint instead of settings.

Tool / setting	What it does	Shortcut	Touch equivalent
Line: Width	Set the stroke width from 1 to 4 pixels.	None	Select a Width.
Rectangle / Oval: Style and Width	Choose Outline or Filled, and a 1 to 4 pixel stroke width.	None	Select Style and Width.
Line: Snap angles	Constrain the line's direction.	Hold Shift while drawing	Tap Snap angles.
Rectangle: Square / Oval: Circle	Keep width and height equal.	Hold Shift while drawing	Tap Square or Circle.
Line: Cancel line	Abandon a line in progress; enabled only while drawing one.	Esc	Tap Cancel line.
Brush: Tip	Round makes a solid tip; Speckle makes a scattered mark.	None	Tap a tip.
Brush: Size and Flow	Size sets the tip's reach from 1 to 4; Flow controls how densely pixels are painted, from 0 to 100%.	None	Select Size; drag Flow.
Erase: Size and Flow	Size sets the eraser's reach from 1 to 4; Flow controls how densely pixels are removed.	None	Select Size; drag Flow.
Select / Select oval: clipboard and Erase selection	Copy, cut, paste or remove selected pixels.	See Edit commands	Tap the command.
Move: Nudge	Shift pixels one pixel in the chosen direction.	Arrow keys	Tap a direction arrow.
Transform: All layers	Include all layers in the transform.	None	Tap All layers.
Transform: Keep proportions	Preserve the ratio of width to height while resizing.	Hold Shift	Tap Keep proportions.
Transform: Flip & rotate	Open commands to reverse or rotate pixels.	None	Tap the menu, then a command.
Transform: Apply / Cancel	Commit the transform or discard its pending changes.	Enter / Esc	Tap Apply / Cancel.
Zoom: Zoom out	Switch canvas taps from enlarging to shrinking the view.	Hold Alt while clicking	Tap Zoom out.
Zoom: Fit / 100%	Fit the canvas into the available space or return to its base display size.	Ctrl+Shift+J for Fit; none for 100%	Tap Fit / 100%.

The canvas-footer hint describes the current tool. Transform status also appears there; on a phone this footer is below the canvas. Status and hints have no shortcut or touch action: read them to see what the tool is waiting for.

Undo and Redo are commands in the tool bar, not settings. See Edit commands.