Lync Online allows you to invite anyone to a meeting you schedule. All you need to do is schedule a meeting as you would in either Outlook or the Lync Web Scheduler and send them the URL for that meeting.
When they receive this link and click on it they will gain access to the meeting. If they already have a Lync Online account and Lync client software (either from Office 2013 or Lync Basic) on their desktop, the meeting will be launched in these applications. If they don’t have a Lync Online account with Lync desktop software, a browser will launch and they can use the Lync Web App to connect to the meeting.
Here’s a video from Office 365 MVP Darrel Webster that steps you through the experience of connecting using a web browser:
Here are some handy links on the Lync Web App:
There are some slightly different limits on what Lync can do across the plans and you’ll find that information here:
You can have up to 250 meeting participants and here a good guide on the best practices when it comes to a Lync Meeting:
This makes Lync Online a really compelling tool for smaller businesses because it can:
1. Reduce the amount of email people have to deal with since they can now quickly chat
2. Allow them to host full blown webinars that can be recorded and used later
3. Provide the ability to see what every one is doing via their presence in Lync
4. Have the same Lync experience on their mobile device and where ever they are.
5. Allow them to remain in contact with their team no matter where they connect from.
So remember, Lync is for all users, even those without Office 365 whom you wish to involve in a meeting. For them access is as simple as using a web browser.