Simple sliding transitioning for navigation controller mimics pre iOS7 push/pop animations.All you need, is simply set delegate for you navigation controller: self.navigationController.delegate = self.navigationTransitioningDelegate;NavigationController does not retain delegate, so you should hold it. Note: this code is free (http://unlicense.org)

MGNavigationTransitioningDelegate.h

//
//  MGNavigationTransitioningDelegate 
//
//  Created by Philip Vasilchenko on 27.11.13.
//

#import <UIKit/UIKit.h>


@interface MGNavigationTransitioningDelegate : NSObject <UINavigationControllerDelegate>

@property (nonatomic, strong) id<UIViewControllerAnimatedTransitioning> pushTransitioning;
@property (nonatomic, strong) id<UIViewControllerAnimatedTransitioning> popTransitioning;

@end

MGNavigationTransitioningDelegate.m

//
//  MGNavigationTransitioningDelegate 
//
//  Created by Philip Vasilchenko on 27.11.13.
//

#import "MGNavigationTransitioningDelegate.h"
#import "MGSlideAnimatedTransitioning.h"


@implementation MGNavigationTransitioningDelegate

- (id)init {
    self = [super init];
    if ( self ) {
        self.pushTransitioning = [MGSlideAnimatedTransitioning transitioningWithReverse:NO];
        self.popTransitioning = [MGSlideAnimatedTransitioning transitioningWithReverse:YES];
    }
    return self;
}


- (id<UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController
                                  animationControllerForOperation:(UINavigationControllerOperation)operation
                                               fromViewController:(UIViewController*)fromViewController
                                                 toViewController:(UIViewController*)toViewController {

    return operation == UINavigationControllerOperationPush ? self.pushTransitioning : self.popTransitioning;
}

@end

MGSlideAnimatedTransitioning.h

//
//  MGSlideAnimatedTransitioning 
//
//  Created by Philip Vasilchenko on 27.11.13.
//

#import <UIKit/UIKit.h>


@interface MGSlideAnimatedTransitioning : NSObject <UIViewControllerAnimatedTransitioning>

@property (nonatomic, assign) BOOL reverse;

- (instancetype)initWithReverse:(BOOL)reverse;
+ (instancetype)transitioningWithReverse:(BOOL)reverse;

@end

MGSlideAnimatedTransitioning.m

//
//  MGSlideAnimatedTransitioning
//
//  Created by Philip Vasilchenko on 27.11.13.
//

#import "MGSlideAnimatedTransitioning.h"


@implementation MGSlideAnimatedTransitioning

static const NSTimeInterval kMGSlideAnimatedTransitioningDuration = 0.3f;

#pragma mark - Initialization

- (instancetype)initWithReverse:(BOOL)reverse {
    self = [super init];
    if ( self ) {
        self.reverse = reverse;
    }
    return self;
}


+ (instancetype)transitioningWithReverse:(BOOL)reverse {
    return [[self alloc] initWithReverse:reverse];
}


#pragma mark - Transitioning

- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext {
    NSString * fromKey = UITransitionContextFromViewControllerKey;
    NSString * toKey = UITransitionContextToViewControllerKey;
    UIViewController * fromViewController = [transitionContext viewControllerForKey:fromKey];
    UIViewController * toViewController = [transitionContext viewControllerForKey:toKey];

    UIView * containerView = [transitionContext containerView];
    UIView * fromView = fromViewController.view;
    UIView * toView = toViewController.view;

    NSTimeInterval duration = [self transitionDuration:transitionContext];
    CGFloat viewWidth = CGRectGetWidth(containerView.frame);
    __block CGRect fromViewFrame = fromView.frame;
    __block CGRect toViewFrame = toView.frame;

    toViewFrame.origin.x = self.reverse ? -viewWidth : viewWidth;
    toView.frame = toViewFrame;
    [containerView addSubview:toView];

    [UIView animateWithDuration:duration
                          delay:0
                        options:UIViewAnimationOptionCurveEaseInOut
                     animations:^{
                         toViewFrame.origin.x = CGRectGetMinX(containerView.frame);
                         fromViewFrame.origin.x = self.reverse ? viewWidth : -viewWidth;
                         toView.frame = toViewFrame;
                         fromView.frame = fromViewFrame;
                     }
                     completion:^(BOOL finished) {
                         if ( self.reverse ) { [fromView removeFromSuperview]; }
                         [transitionContext completeTransition:![transitionContext transitionWasCancelled]];
                     }];
}


- (NSTimeInterval)transitionDuration:(id<UIViewControllerContextTransitioning>)transitionContext {
    return kMGSlideAnimatedTransitioningDuration;
}

@end

Can you please tell me how to use these classes in my project ?

Hello,
Although this brought back the transition I needed, if I rotated my app after using the transition and then transitioned back, the frame would be the "old" frame and not the new rotation. I had to make this change to make sure I was transitioning back to the proper view:
//__block CGRect toViewFrame = toView.frame;
__block CGRect toViewFrame = [transitionContext finalFrameForViewController:toViewController];