MapKit callout bubble pop animation

gistfile1.m

self.view.layer.anchorPoint = CGPointMake(0.50, 1.0);
CAKeyframeAnimation *bounceAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.scale"];

bounceAnimation.values = [NSArray arrayWithObjects:
                          [NSNumber numberWithFloat:0.05],
                          [NSNumber numberWithFloat:1.08],
                          [NSNumber numberWithFloat:0.92],
                          [NSNumber numberWithFloat:1.0], 
                          nil];

bounceAnimation.duration = 0.3;
[bounceAnimation setTimingFunctions:[NSArray arrayWithObjects:
                                      [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                      [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                      [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                      [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut], 
                                      nil]];
bounceAnimation.removedOnCompletion = NO;
    
[self.view.layer addAnimation:bounceAnimation forKey:@"bounce"];

I analyzed UICalloutView "under a microscope" while it animated, inspecting its sequence of CABasicAnimations as it appeared, and I believe this is the exact sizing+timing sequence:

CAKeyframeAnimation *bounceAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.scale"];
CAMediaTimingFunction *easeInOut = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];

bounceAnimation.values = @[@0.05, @1.11245, @0.951807, @1.0];
bounceAnimation.keyTimes = @[@0, @(4.0/9.0), @(4.0/9.0+5.0/18.0), @1.0];
bounceAnimation.duration = 0.3;
bounceAnimation.timingFunctions = @[easeInOut, easeInOut, easeInOut, easeInOut];