Get sub page or child page name in tabs page

This should answer your question

getSelected();
//Returns: Tab
//Returns the currently selected tab

EDIT: Im not sure but:
Do you mean that PAGE B isn’t a Tabpage at all ? And you want to replace the Tabname PAGE A to PAGE B ?

If so you need to pass parameters to Tabs.ts when entering PAGE B and replace the strings.

As quick example how it could look like:

HTML:
<ion-tab [root]="tab1Root" tabTitle="{{TAB1}}" tabIcon="ios-home"></ion-tab>

TS TABS

export class TabPage{
  TAB1 = "PAGE A"; 
  //This string is to replace when you push a parameter.
}

NavParams Doc: