$windows.alert() on iPhone running IOS 10

Using Ionic 1.

The alert message is displayed however above the message is a line in bold titled ‘index.html’.

Does anyone know why?

because you are using the standard browser alert and it shows the web address in the header/title. In this case, index.html. Use the Ionic Popup http://ionicframework.com/docs/api/service/$ionicPopup/ It works in the browser and on mobile. You can set the title and message, even use html in the body.