As you can see on the webphone pricing page, the software is mainly licensed per server. The Standard license allows the usage with one single server and the Advanced license allows up to 4 servers.

However we also have a Gold license which is much more flexible regarding the licensing.

If you don't have your own limited number of SIP servers or if you are developing an app which you wish to sold to others with freely configurable SIP server address, then most probably you should opt for a Gold license.

 

With the Gold license we can allow one of the followings:

Contact us about the possibilities or if you are in doubt. We are open also for other solutions. The most important thing is that we would like to avoid unautorized usage by publishing a license which potentially can be downloaded and freely used elsewhere.
 

Of course, the number of users and calls are unlimited. (This is already unlimited in the Advanced version)