I'm trying to replicate this blurred background from Apple's publicly released iOS 7 example screen:
This question suggests applying a CI filter to the contents below, but that's a whole different approach. It's obvious that iOS 7 doesn't capture the contents of the views below, for many reasons:
Can anyone hypothesize what frameworks they could be using to create this effect, and if it's possible to create a similar effect with current public APIs?
Edit: (from comment) We don't exactly know how Apple is doing it, but are there any basic assumptions we can make? We can assume they are using hardware, right?
Is the effect self-contained in each view, such that the effect doesn't actually know what's behind it? Or must, based on how blurs work, the contents behind the blur be taken into consideration?
If the contents behind the effect are relevant, can we assume that Apple is receiving a "feed" of the contents below and continuously rendering them with a blur?
Why bother replicating the effect? Just draw a UIToolbar behind your view.
myView.backgroundColor = [UIColor clearColor];
UIToolbar* bgToolbar = [[UIToolbar alloc] initWithFrame:myView.frame];
bgToolbar.barStyle = UIBarStyleDefault;
[myView.superview insertSubview:bgToolbar belowSubview:myView];