How to check if the user has the application installed in the browser?

Question

Mobile development

There is a link on the web:

<a href="fb://page?id=116394476653632970"><img src="/social_sms/fb.png"></a>

When you click on it, the browser shows the user a message: "Open in "Facebook"?". If you click yes, the installed Facebook application and a specific page are opened.
Everything would be fine, but:

• If there is no installed application, the browser displays a message stating that there is no such link;
  
• On iOS, it works in almost all normal browsers. On Android, if the app is installed, the Facebook app opens, but not the specific page.
  

Questions:

1. How to check the presence of a pre-installed application so that, in cases where there are no applications, change the link "fb://page?id=116394476653632970" to a regular Facebook page link?
   
2. Why doesn't it work on Android?
   

Answer 1

1. stackoverflow.com/a/24571962
2. stackoverflow.com/a/34564284