The client token is an identifier that you can embed into native mobile binaries or desktop apps to identify your app. The client token isn't meant to be a secret identifier because it's embedded in apps.
Your application may use a client token when accessing limited set of resources that are not specific to a user and made available to client device or browser directly. To do this, include client token in the Authorization header as type Token.
Here’s an example request, using the Feed endpoint.