Apps licensed/turned on by default

In general, apps are released in an enabled state when they exit Preview and reach General Availability. You can find the licenses and their on/off state in the Admin Center. I do this by opening up a user and editing the license assigned to him or her. Without making any changes, you can view the state of the app.

I also want to acknowledge the need for authoritative documentation on this topic, and it's something we're discussing within my team.

CC: Anne Michels, Tom Batcheler

I'm not sure such list exists. When it comes to licensing/SKUs/services, my point of reference is usually the following blog post and the comments therein: https://blogs.technet.microsoft.com/treycarlee/2014/12/09/powershell-licensing-skus-in-office-365/

It's getting outdated now though, so perhaps someone (not as lazy as me) can publish something better :)