Android - How to open the Hangout app from a Hangout URL displayed in the webview?

I just made an Android app where I am displaying my website in a webview.
My webpage has many links to Google Hangouts URL (http://ift.tt/1FaSsyH.......) in which there are people in a call. When this link is clicked on a Desktop's browser, the URL gets opened in a new tab and the user is able to join the Google Hangout call.

But when I open the hangout URL in mobile app(webview), it takes me to google play in the my app(webview) and asks me to install hangout which I already have installed.

Instead of going to google play store within my webview,

When Google Hangouts app is installed on the Android phone
1) How do I open the hangout app from my webview activity which has hangout URLs in this form(http://ift.tt/1FaSsyH.......)?

When Google Hangouts app is not installed on the Android phone. 2) How to open Google playstore app and inform the user to Install Google Hangout app in order to join the call?

Kindly help. Thanks.