Back Button problem to tabs

Hello Sir
I have map. there is a header on the top and back left header.Below the image
image w

when i click the back button it has a error :Error: ctrlB is null in the browser console. But when i run the app to ipone Back button is disable.

Note: I have used tabs. That means when i click back button it goes a view where i have used tabs.

Please help me…