viewWillAppear
 viewWillDisappear
 viewDidAppear
 viewDidDisappear

 viewDidLoad
 viewDidUnload
 viewWillUnload

– viewDidUnload Deprecated in iOS 6.0
– viewWillUnload Deprecated in iOS 6.0

Configuring a GLKit view
- (void)viewDidLoad
{
    [super viewDidLoad];

    // Create an OpenGL ES context and assign it to the view loaded from storyboard
    GLKView *view = (GLKView *)self.view;
    view.context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];

    // Configure renderbuffers created by the view
    view.drawableColorFormat = GLKViewDrawableColorFormatRGBA8888;
    view.drawableDepthFormat = GLKViewDrawableDepthFormat24;
    view.drawableStencilFormat = GLKViewDrawableStencilFormat8;

    // Enable multisampling
    view.drawableMultisample = GLKViewDrawableMultisample4X;
}


Simple Core Animations 3D transform of UIView

CATransform3D rotationAndPerspectiveTransform = CATransform3DIdentity;
rotationAndPerspectiveTransform.m34 = 1.0 / -1000.0;
rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform, M_PI * 0.6, 1.0f, 0.0f, 0.0f);
[UIView animateWithDuration:1.0 animations:^{
    self.someView.layer.anchorPoint = CGPointMake(0.5, 0);
    self.someView.layer.transform = rotationAndPerspectiveTransform;
} completion:^(BOOL finished){
    // code to be executed when flip is completed
}];