Create a link that either launches iOS app, or redirects to app store [duplicate]

Answer 1

There is no good way to achieve this. You can launch an app via a URL but there is no way to test whether an app is installed first.

Answer 2

 window.launchsockPicker = function() {
       setTimeout(function() {
        window.location = 'http://myDomain.com/install-app.cfm'
       }, 500);

       window.location = 'myApp://?context=someVariableIfNeeded';
   };