You have to get .ipa file and .plist manifest file with required details and upload it to a location in Azure server.

Since ipa and .plist file extensions are not recognised by Azure server so if you try to click on the ipa download link you would get the error unabled to download. 

To fix this we have to add following extensions into server MIME types

.ipa – application/octet-stream

.plist – text/xml

You can add these MIME Type directly to the web.config file

<system.webServer>
    <staticContent>
      <mimeMap fileExtension=".ipa" mimeType="application/octet-stream" /> 
      <mimeMap fileExtension=".plist" mimeType="text/xml" /> 
    </staticContent>   
</system.webServer>