Depends on what you want to 'manage'.
It is possible to keep data client side in places called 'sessionStorage' (for temporary data during the session) and 'localStorage' (which should be the app's permanent storage area). The size of both is limited, but usually large enough for data you need to drag along while using the app.
See for instance:
Using these data areas, you can read and write pieces at any time, and send them to the server with any ajax request. That would allow the server to receive a token or identifying information from the client for verification or identification.