Yes, you can send out a fully customized email to your clients after their appointments. You can set the exact number of minutes that after the appointment ends to send out the follow up automatically (even if you want it to go out weeks after the appointment).
To set up your follow up email, go to Settings -> Customize Emails/Texts.
Then from the list of messages, click on the "Appointment Follow Up"
Here you can customize the exact content of the email, and also activate the follow up email and set how long after each appointment it should be sent.