If you set the drawsAsynchronously or acceleratesDrawing property on a CALayer (the former is public and the latter is private), then the CGContext passed to yo

If you set the drawsAsynchronously or acceleratesDrawing property on a CALayer (the former is public and the latter is private), then the CGContext passed to you in -[CALayer drawsInContext:] or -[UIView drawRect:] will be GPU-accelerated in the same way. WebKit on iOS uses this to accelerate 2D rendering. Having said this, don't go turning this on everywhere, like on every tiny little UILabel. That GPU-accelerated CGContext is rendered in an offscreen pass using render-to-texture so it is often faster to use the CPU. This property was more designed for, say, a full-screen drawing app on a retina iPad that uses a a single screen-sized CGContext for its drawing canvas, or for the Safari case where there are a number of same-sized CGContext tiles to draw into.