ShakeAnimation; a variant on @danielctull's versopm

ShakeAnimation.m

@implementation ShakeAnimation {
  CGRect originalRect;
  NSInteger counter;
}

+ (void)shakeView:(UIView *)view {
  [[[[self class] alloc] initWithView:view] shake];
}

- (id)initWithView:(UIView *)view {
  self = [super init];
  if (self) {
    self.view = view;
    originalRect = view.frame;
    counter = 20;
  }
  return self;
}

- (void)shake {
  [self.view addFrameX:5];
  [self shakeWithDirection:-1 completion:^{
    self.view.frame = originalRect;
  }];
}

- (void)shakeWithDirection:(NSInteger)flip completion:(dispatch_block_t)completion {
  [UIView animateWithDuration:0.05f animations:^{
    [self.view addFrameX:10 * flip];
  } completion:^(BOOL finished){
    counter--;
    if (counter == 0)
      completion();
    else
      [self shakeWithDirection:flip * -1 completion:completion];
  }];
}

@end