I’ll admit that I’m not totally on time with this post but I only noticed that update for the Lync 2013 app today – Better late than never they say right?
http://www.windowsphone.com/en-gb/store/app/lync-2013/d85d8a57-0f61-4ff3-a0f4-444e131d8491
It appears that Microsoft have listened to the feedback of the many and added some new features to the Lync 2013 app, most notably, the ability to use the app to join a Lync Online Meeting without needing be a Lync user yourself.
This is something I asked for in my feedback on the app when it was first launched so it’s great to see. I use Lync daily in the office for IM and presence, however we haven’t got as far as a fully edge published solution for external online meeting capability which means I’ve previously not been able to sign in and use the Lync app. Thanks to this latest update, you can now use the app to join an online meeting as a guest attendee.