My app has to load from the 2nd tab as per my code. Its working fine in all iOS except iOS6.
I am using [appDelegateObj.tabBarController setSelectedIndex:1];
When I run it in iOS6, mid-tab gets highlighted and services at both 1st and 2nd tab starts loading and finally gets jammed showing just the loading symbol.
I Suggest you to check example of UITabBar of developer.apple.com in your IOS6 deployment environment.
On top of that try setting selectedIndex of your UITabBarController, like this:
Hope this helps…