It's very simple to add Smartarget apps to you Wix website, in fact it takes less than 3 min
Once you finished to setup your Smartarget account (which takes few minutes only), go to Integration and copy the code-line
1. Go to Settings
2. Click the Custom Code tab in the Advanced section.
3. Click + Add Custom Code at the top right.
4. Paste the code snippet in the text box.
5. Enter a name for your code: Smartarget WhatsApp
6. Select an option under Add Code to Pages: All pages
7. Choose where to place your code under Place Code in: Body End
8. Click Apply