Yes, you may use PrivateTunnel on as many devices as you'd like, however individual accounts are allow a maximum of 3 devices to be connected to the service at the same time. Our Flexible accounts include the option to add more devices for a charge.
To prevent unauthorized usage of your account, you are discouraged from connecting using a public computer (such as that in a library or a kiosk) or a shared computer where incidental usage may not be welcome (e.g. one-time use on a friend's machine).