Universal Email Marketing Deep Links in CommentSold automatically direct shoppers from marketing emails to the most relevant shopping destination. If a shopper has your mobile app installed and is using version 4.6.0 or later, links can open directly in the app. Otherwise, shoppers are directed to your web store. Learn how to configure universal email deep links with Klaviyo, register your click tracking subdomain, upload app association files, and troubleshoot setup issues.
Use the table of contents below to navigate to specific sections of this article:
- Requirements
- Customer Experience
- Setup instructions for Klaviyo
- What's Next?
- Expected Behavior
- FAQs
- Troubleshooting
Requirements
Custom domain requirement: This feature requires you to have a custom domain set up in CommentSold. See our Custom Domain Setup article for more information.
Mobile version requirement: This feature requires your shop's mobile app to be on version 4.6.0 or newer. Your customers' apps must also be on version 4.6.0 or later to receive the enhanced experience.
Customer Experience
-
App installed
Email link opens directly in the native mobile app, sending shoppers straight to the product or page. -
App not installed
Link falls back seamlessly to your web store—no broken experiences for new or web-only shoppers. -
5x higher conversion
Native app experiences are proven to convert at significantly higher rates than mobile web.
Setup instructions for Klaviyo
Setup involves four parties: your mobile app, your CS Admin, your email marketing platform (e.g. Klaviyo), and your customers' apps. Follow each step in order.
Step 1: Configure your email sending domain in Klaviyo
- You may already have your branded sending domain configured.
- If you haven't set this up, follow Klaviyo's branded sending domain guide to complete this step before proceeding.
Step 2: Set up a click tracking subdomain in Klaviyo
This is a dedicated subdomain used to track clicks in your marketing emails (e.g. trk.send.myshop.com).
You'll need to contact Klaviyo support via email to enable this for you. Here's how:
- From within your Klaviyo account, click Support
- Click Email Support and complete the fields as instructed below.
- Category: Account Settings
- Subcategory: Sending Domains
- Click No, submit a request
- Subject: Click Tracking Domain
- What do you need help with: "I have setup my branded sending domain and now I am reaching out to support to have a click tracking domain with SSL enabled for my account."
- Click Submit
If you have any questions, follow Klaviyo's click tracking subdomain guide to complete this step.
Step 3: Register your click tracking subdomain in CS Admin
Once your subdomain is ready in Klaviyo, register it with CommentSold:
- Go to your CS Admin dashboard
- Navigate to Setup → Custom Domain
- Enter your click tracking subdomain obtained from Klaviyo support (e.g.
trk.send.myshop.com) in the Click Tracking Subdomain field. - Click Save
Step 4: Download app association files from CommentSold
After saving your subdomain, you'll see two buttons appear directing you to download files. These files tell the operating system that your click tracking subdomain is trusted to open your mobile app.
- Click each one to download the two required app association files from CS Admin:
- The Android Asset Links button will download
.well-known/assetlinks.json— for Android - The Apple App site Association button will download
.well-known/apple-app-site-association— for iOS
- The Android Asset Links button will download
Step 5: Upload app association files to Klaviyo
- In your Klaviyo account, navigate to Settings → Push Notifications → Universal & app links
- Upload both downloaded files to Klaviyo using their app association file upload flow. This links your tracking subdomain to your iOS and Android apps at the platform level.
If you get stuck, follow Klaviyo's guide for uploading association files to complete this step.
Step 6: Request an app rebuild from CommentSold
- Contact CommentSold support and request an App Rebuild for Universal Email Deep Links.
- The support team will submit your request to the app team.
Once the mobile team has processed your request, it can take 24-48 hrs for Google and Apple to approve your new app build. The entire process may take up to four days.
What's Next?
- After CommentSold rebuilds your app with the click tracking subdomain, install the latest app version on your phone and encourage your customers to do so as well.
- Check the bottom of the account page within your app to confirm which version you're on.
- If you are not on version 4.6.0 or higher, make sure your developer accounts are up to date.
- Your customers must also be on this version to experience deep linking.
- Send a test campaign to a device with the updated app installed and verify that email links open directly in the app. Also test on a device without the app to confirm the web store fallback works correctly.
Expected Behavior
Once setup is complete, here's what you and your customers can expect:
- Marketing email links using your configured tracking subdomain will open in the app for customers on app version 4.6.0+
- Customers who have not installed the app, or are on an older version, will be taken to your web store instead.
- You can use any commentsold deep link across all marketing emails.
FAQs
What are Universal Email Marketing Deep Links?
Universal Email Marketing Deep Links direct shoppers from marketing emails to the most relevant shopping destination. Shoppers with a compatible mobile app can open links directly in the app; others are directed to your web store.
What are the requirements for universal email deep links?
You must have a custom domain configured in CommentSold, and your shop's mobile app and your customers' apps must be running version 4.6.0 or later.
Does my shop need a custom domain?
Yes. A custom domain must be configured in CommentSold before you set up universal email deep links.
Why do I need a click tracking subdomain?
The click tracking subdomain connects your email links to your mobile app, allowing supported devices to recognize the app as a trusted destination.
Can I configure universal email deep links without Klaviyo support?
The setup instructions require you to contact Klaviyo support to enable a click tracking subdomain with SSL before registering it in CommentSold.
Where do I register my click tracking subdomain?
In CS Admin, go to Setup > Custom Domain, enter the subdomain in the Click Tracking Subdomain field, and select Save.
Which app association files do I need?
You need both files:
-
assetlinks.jsonfor Android. -
apple-app-site-associationfor iOS.
Download both files from CS Admin and upload them to Klaviyo through its Universal & app links settings.
How long does an app rebuild take?
After you request an app rebuild from CommentSold, Apple and Google approval may take 24–48 hours after the mobile team processes the request. The full process may take up to four days.
What happens if a shopper doesn't have the mobile app installed?
The link directs the shopper to your web store instead of opening the app.
Will deep links work for customers using an older app version?
Customers using an app version older than 4.6.0 will be directed to your web store rather than receiving the enhanced in-app experience.
How do I test universal email deep links?
Send a test marketing campaign to a device with the updated app installed and verify that links open in the app. Also test on a device without the app to confirm that links open your web store.
What should I check if email links don't open the app?
Confirm that the shop and customer apps are version 4.6.0 or later, the click tracking subdomain matches in Klaviyo and CS Admin, both association files are uploaded, your emails use the configured tracking subdomain, and Klaviyo has activated the subdomain.
Troubleshooting
If deep links are not opening the app as expected, work through the following checks:
- Confirm the app version is 4.6.0 or later on both the shop and customer device.
- Verify the click tracking subdomain in CS Admin exactly matches the subdomain configured in Klaviyo.
- Confirm both
assetlinks.jsonandapple-app-site-associationfiles have been uploaded to Klaviyo. - Check that your marketing emails are using the configured subdomain for all links (not a legacy tracking domain).
- If you submitted a support request to Klaviyo for the click tracking subdomain, confirm it has been approved and activated.