iPhone: How to hide tab bar to show fullscreen view
[self.navigationController setNavigationBarHidden:activated animated:YES];

CATransition *animation = [CATransition animation];
[animation setType:kCATransitionFade];
[[self.view.window layer] addAnimation:animation forKey:@"layerAnimation"];
[self.tabBarController.tabBar setHidden:YES];

// Display tab bar animated
CATransition *animation = [CATransition animation];
animation setType:kCATransitionFade];
[[self.view.window layer] addAnimation:animation forKey:@"layerAnimation"];
[self.tabBarController.tabBar setHidden:NO];

[[self navigationController] setHidesBottomBarWhenPushed:YES];

self.hidesBottomBarWhenPushed = YES;
this will hide the tabbar

tabBarController.tabBar.hidden = YES