Schedulista lets you pass client data to the Scheduler via URL parameters.

The following parameters are accepted:

All parameters are optional. Parameters must be URL-encoded.

Example:
 http://salon.schedulista.com/?first_name=Felix&last_name=Livni&email=felix@schedulista.com&phone=(800)%20419-1672

If you click on the link above and go through the scheduler, you will see that all the client fields are pre-filled for you.