You can activate Call waiting in your Telavox mobile app through Settings > Incoming calls > When busy > Call waiting. Also remember to activate call waiting in the phone's own settings. You should therefore have calls waiting active both via Telavox and in the mobile phone itself. The same applies if you want the function disabled, then it should be disabled on both.
When call waiting is activated, you can receive a call even if you are already in another one. If you have problems, you can try restarting your mobile phone.
Tip!
If you're having trouble finding the Call waiting setting on your mobile phone, you can also call *43# to activate call waiting in the mobile. Or #43# to disable it. If you would experience any problems with activating call waiting with these codes, please try to set your phones mobile network settings to 2G/3G only and try to activate it again. If it works, you can then switch back to the mobile network settings of your choice.