How many devices can I use the soft client on?

The softphone client is available for three device groups (devices): Workstation PC, Smartphone Apple IOS and Smartphone Android.
You can install the softphone client Cisco WebEx on all three devices and run it in parallel.
However, you can only actively use one device per device group. Example: If you have two smartphones with Apple IOS, you can install the softphone client on both smartphones but only actively use the telephony function on one device; the other device is logged off in each case.