If you plan to share content with other attendees in a Lync Meeting, you’ll need to connect to the meeting by using Lync on your desktop computer.
If you’ve joined a meeting from your mobile device, and then you join the same meeting from your desktop computer, you’ll stay connected to the meeting audio on your mobile phone and connect to the visual part of the meeting on your desktop computer.
We recommend that you only connect to the meeting audio and video on either your mobile device or your desktop computer.