DPI (dots per inch) measures how many pixels (dots) occur in each inch of your artwork when you print it. As of now, the Drawing app produces drawing with 72dpi.
If you create a canvas using a physical measurement, then the DPI controls how large the canvas will be in pixels. If you create a canvas using pixels, then the DPI controls how large it will be on print.
A higher DPI means more pixels per inch which also means a higher quality print. The smaller the artwork, the greater the pixel density required to produce a high-quality print.
The larger your intended print, the less DPI you can have, as it is likely a large work will be viewed from further away and will therefore not need as much fine detail as something to be viewed at arm’s length. A canvas of 2 meters by 1 meter (200cm x 100cm) could produce a great print at 100dpi. Billboards often have a DPI as low as 12 or 15.
Do you wish to have a custom setting to set your own DPI level for your canvas? Please raise the request through support. If we get many such requests, we will surely plan and introduce it in the upcoming version.