when receive push notification, want navigation controller first view. tab bar recognized, however, navigation controller not move back.
- (void)application:(uiapplication *)application didreceiveremotenotification:(nsdictionary *)userinfo { if (application.applicationstate == uiapplicationstateinactive){ uitabbarcontroller *tabb = (uitabbarcontroller *)self.window.rootviewcontroller; tabb.selectedindex = 0; uinavigationcontroller *nav = (uinavigationcontroller *)tabb.navigationcontroller; [nav poptorootviewcontrolleranimated:yes]; } } 
i;n line, you're saying want access uinavigationcontroller contains tab controller.
uinavigationcontroller *nav = (uinavigationcontroller *)tabb.navigationcontroller; however, appears want access navigation controller contained in tab controller.
since first controller can access so:
uinavifationcontroller *nav = (uinavifationcontroller *)[tabb.viewcontrollers objectatindex:0]; 