When you get a Lync call it will look the same as any other call you get on your Windows Phone. The only difference is that when you get the call, the ringtone will be the default Lync ringtone (this ringtone can’t be changed), and the incoming call screen will have a Lync logo on the left.
Depending on how you set your VoIP call options, when you make or receive an audio call it might use Wi-Fi or your cellular data plan. For more information, go to Adjust your data use settings.
If your incoming calls are going to voice mail too quickly, we recommend that you increase your voice mail timer setting to at least 30 seconds. This will give you more time to answer an incoming call before it goes to voice mail.