Pixel aligns rectangles, taking the device's screen scale into account.

CGRectIntegralScaled.m

CGRect CGRectIntegralScaledEx(CGRect rect, CGFloat scale)
{
    return CGRectMake(floorf(rect.origin.x * scale) / scale, floorf(rect.origin.y * scale) / scale, ceilf(rect.size.width * scale) / scale, ceilf(rect.size.height * scale) / scale);
}

CGRect CGRectIntegralScaled(CGRect rect)
{
    return CGRectIntegralScaledEx(rect, [[UIScreen mainScreen] scale]);
}

CGRect CGRectIntegralMake(CGFloat x, CGFloat y, CGFloat width, CGFloat height)
{
    return CGRectIntegralScaledEx(CGRectMake(x, y, width, height), [[UIScreen mainScreen] scale]);
}