This made me smile. It’s an interesting question. It’s not unlike asking what people actually use spreadsheets for? Or Word - what’s that good for? 
Less enlightened people might get that impression.
At Stream It we have a very different feeling. We use it for about 20 different processes mostly related to measuring AI performance of highway analytics systems. We also use it to gauge automation projects.
This is a Coda “app”. It helps our team collect, analyze, and report AI precision for highway data. It tests a system that collects about a billion vehicle events per year.
This is a Coda “app” as well. Sorry for the redactions. The legal department is where fun goes to die.
And this is also a Coda app. Who new it could serve in a DevOps role?
