Add me to the haven't heard of them list. Mind you I almost hadn't heard of Crowdstrike and they managed to brick the world.
Do you know of Active Directory? Most have no idea, even though it is a Windows Server feature from 2000.
Some will live a life and even work not knowing.
Samba can act as an AD DC.
And to be honest, it's fairly understandable. AD manages to be somewhat turnkey while doing the same thing on Linux systems is a major pain.
When I played with it I stayed away from self-managing something like it for linux-only systems and for mixed/cloud/online systems I use Entra Id
I am fairly convinced that Redhat, Novel and Oracle probably have a nice interface on top of it all to make it manageable and therefore have a vested interested in keeping it as awful as possible for the rest of the world.
If you work on internal company systems in a Microsoft environment it often can be.
What sector is the app in, what are some other interesting (non-identifying) aspects of the app that stand in contrast to revenue? Is that in ads, or does the app have in-app purchases et al?