Enable or disable sub-pixel anti-aliasing. When designing for the Mac or the web you will want to leave this one, when designing for iOS you’ll want to turn this off.
Note: If the system preference “Use LCD font smoothing when available” is off, the in-app font rendering preference will have no effect.
Read more about sub-pixel anti-aliasing in here.
Retina screens for Mac and iOS use four physical pixels to represent one ‘traditional’ pixel. Retina Mac devices have four-times as many pixels as the older models, but display everything at the same size. They just use these extra pixels to provide more detail to fonts, images etc.
By default Sketch does the same; the extra pixels are used to provide more detail, but the physical size of the drawing stays the same. If you don’t want this behaviour and really want every physical pixel to be counted as one pixel in sketch, turn off the Retina Canvas preference.
The animated zoom will provide context from where you have zoomed from. If off, your document will update to the new zoom level with no transition.
Zoom In On Selection
When you tell Sketch to zoom in via the View › Zoom In / Zoom Out commands, Sketch will by default zoom into the center of the canvas. By turning on this checkbox it will instead focus in on the selected layers.
Zoom Back to Previous Canvas Position
Using this option, Sketch will zoom out to the position you had on the canvas before you started zooming in. By default when you zoom out, Sketch zooms back straight from the center point currently on canvas, but if you scroll around a lot while zoomed in and you expect to return to the previous position on zoom out, use this checkbox.
The color selected in the preferences will be visible if the Smart Guides option is on, and appear when layers align, or when measuring whilst holding Option.