Adds an animation to a view. Then monitors `viewWillAppear` and `appWillEnterForeground` to re-add the animation whenever necessary.

UIViewController+AlwaysAnimation.h

#import <UIKit/UIKit.h>

@interface UIViewController (AlwaysAnimation)

- (void) alwaysAnimate:(CABasicAnimation*)animation view:(UIView*)view;

@end

UIViewController+AlwaysAnimation.m

//
//  UIViewController+animation.m
//  Speaky
//
//  Created by Joshua Wright on 5/19/13.
//  Copyright (c) 2013 Joshua Wright. All rights reserved.
//

#import "UIViewController+AlwaysAnimation.h"
#import <QuartzCore/QuartzCore.h>
#import <objc/runtime.h> 


@interface AlwaysAnimation : NSObject
@property (retain) CABasicAnimation* animation;
@property (weak) UIView* view;
- (void) addAnimation;
@end
@implementation AlwaysAnimation
- (void) addAnimation
{
    [self.view.layer addAnimation:self.animation forKey:@"alwaysAnimated"];
}
@end


@implementation UIViewController (AlwaysAnimation)

- (void) reAddAlwaysAnimations
{
    NSMutableArray* animations = objc_getAssociatedObject(self, "alwaysAnimations");
    for(AlwaysAnimation* animation in animations){
        [animation addAnimation];
    }
}

- (void) viewWillAppear_AlwaysAnimation:(BOOL)animated
{
    [self viewWillAppear_AlwaysAnimation:animated];
    
    [self reAddAlwaysAnimations];
}

- (void) viewDidUnload_AlwaysAnimation
{
    [self viewDidUnload_AlwaysAnimation];
    
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    objc_setAssociatedObject(self, "alwaysAnimations", nil, OBJC_ASSOCIATION_RETAIN);
}

- (void) alwaysAnimate:(CABasicAnimation*)animation view:(UIView*)view
{
    NSMutableArray* animations = objc_getAssociatedObject(self, "alwaysAnimations");
    
    if(animations == nil)
    {
        //viewWillAppear
        method_exchangeImplementations(
           class_getInstanceMethod([self class], @selector(viewWillAppear:)),
           class_getInstanceMethod([self class], @selector(viewWillAppear_AlwaysAnimation:)));
        
        //viewDidUnload
        method_exchangeImplementations(
           class_getInstanceMethod([self class], @selector(viewDidUnload)),
           class_getInstanceMethod([self class], @selector(viewDidUnload_AlwaysAnimation:)));
        
        if(animations == nil){
            animations = [NSMutableArray array];
            objc_setAssociatedObject(self, "alwaysAnimations", animations, OBJC_ASSOCIATION_RETAIN);
        }
        
        //appEnterForeground
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reAddAlwaysAnimations) name:UIApplicationWillEnterForegroundNotification object:nil];
    }
    
    AlwaysAnimation* alwaysAnimation = [[AlwaysAnimation alloc] init];
    alwaysAnimation.view = view;
    alwaysAnimation.animation = animation;
    [animations addObject:alwaysAnimation];

    [alwaysAnimation addAnimation];
}

@end