This should be included on every page in your app, just before the closing `` tag.
Step 2: Identify your users
The first time `_cio.identify` is called, you must send us the following:
- `id` (that user's unique identifier)
- `created_at` (a timestamp which represents when they first signed up)
- `email` (or other contact attribute)
But you can also send in any additional user attributes that are of value to you. In the above example we are sending the optional attributes `first_name` and `plan_name`. You can use these attributes in the body of an email, or you can use them to segment your users.
Important things to know
We only track activity for users registered in your app, after `_cio.identify` is called. We do not track anonymous or unregistered user activity.
To update an existing user's attributes, just send the `identify` call again. You must include their `id` and any new attribute values - we'll overwrite them. If there are any new ones included in the call, we'll add them as well.