Added more details for anon users (#576)

docusaurus/docs/iOS/03-guides/01-client-auth.mdx

@@ -49,7 +49,7 @@ let streamVideo = StreamVideo(
 )
 ```
 
-And here's an example for an anonymous user
+And here's an example for an anonymous user:
 
 ```swift
 let streamVideo = StreamVideo(
@@ -60,6 +60,29 @@ let streamVideo = StreamVideo(
 )
 ```
 
+Anonymous users don't establish a web socket connection, therefore they won't receive any events. They are just able to watch a livestream or join a call.
+
+The token for an anonymous user should contain the `call_cids` field, which is an array of the call `cid`'s that the user is allowed to join. 
+
+Call `cid` consists of the call type and the call id, in the following format: `callType:callId`.
+
+Here's an example JWT token payload for an anonymous user:
+
+```swift
+{
+  "iss": "@stream-io/dashboard",
+  "iat": 1726406693,
+  "exp": 1726493093,
+  "user_id": "!anon",
+  "role": "viewer",
+  "call_cids": [
+    "livestream:123"
+  ]
+}
+```
+
+If you try to join a call that is not listed in the array, you will receive an error.
+
 ### Client options
 
 Here's a more complete example of the client options: