title: How to track UTM tags in App Store URLs
body: <p>I'm working on implementing my own analytics system. One part of it consists of tracking where users originated from. I use UTM tags for this. Reading UTM tags from the query parameters is quite easy in Android, iOS and web. However, I also want to track app installs.</p>
  
  <p>I want to be able to share URLs to the Play/App store with UTM tags and mark the user's first session in the app with those tags. Android has a great solution for this: pass the <code>referrer</code> query parameter containing the UTM tags to the Play Store URL and after installation, the UTM tags will be available. (source: <a href="https://developers.google.com/analytics/devguides/collection/android/v4/campaigns" rel="noreferrer">https://developers.google.com/analytics/devguides/collection/android/v4/campaigns</a>)</p>
  
  <p>However, the App store doesn't support this kind of tracking. I'm trying to figure out what the industry standard is for tracking app installs. I've seen the following solution:</p>
  
  <ol>
  <li>Share a URL to your own domain. (e.g. myredirectdomain.com?utm_campaign=test)</li>
  <li>Save the client ip, screen resolution and UTM tags in a DB table if the client is an iOS device</li>
  <li>Redirect the user to the App Store</li>
  <li>Once the user installs the app, the app will send the client ip and screen resolution to your server which checks if those are recently added in the DB.</li>
  <li>If so, the corresponding UTM tags are returned and the user's session will be marked with those.</li>
  </ol>
  
  <p>Of course, this will most definitely result in some false positives. I've been trying to figure how other companies do this. I've stumbled upon Google Analytics' implementation which utilizes the iPhones IDFA (source: <a href="https://developers.google.com/analytics/solutions/ios-install-tracking" rel="noreferrer">https://developers.google.com/analytics/solutions/ios-install-tracking</a>). However, the IDFA doesn't seem to be available to the mobile browser.</p>
  
  <p>Do you know what the industry standard is for tracking app install campaigns?</p>