itch.io

That has nothing to do with drm. Steam is an ocean, itch is a puddle. Everyone with a game eglibly to be sold on Steam will try to do so. There is just so much more potential players. Most people do not even know itch exists. If you look at some popular and upcoming games on itch, they have like 100x the reviews on steam than they have followers on itch.

Also, drm is useless in general and especially in the indie sector. You will hurt your legit players more than you might gain by implementing it. Think about it. Will you sell a single unit more, because it was protected? Protection does not sell. Period. No one, literally no one, buys a game because it is drm protected. But there are people, especially in the indie gaming community, that will not buy your game specifically because of some drm. This happens on Steam as well. Certain drm technolgies are hated and people avoid those.

And to put injury to insult, if a game is popular and not some kind of online account game, the drm will be disabled anyways for illict distribution.

Think very hard, if account verification will be a benefit for your players. There are cases where this is true. Like cloud saving or multiplayer interaction and such. The "drm" is only a side effect. 

But enough of my ranting ;-)

I shall reply to the other part in a separate posting...

I also was talking about the desktop application. That is a chromium browser that handles updates and installation and has some helper apps in the background, like that butler. In theory. It does not work properly for all games.

There is a faq about the app, that says this https://itch.io/docs/app/faq#will-the-app-replace-the-website

We want the app to compliment the website, not replace it. 

So if there where mechanics to make the app mandatory for a game, this would be strange.

After cross reading this again, https://itch.io/docs/api/overview , there might actually be the option to have an app that will not work properly without the itch launcher. The use case they imply is for online games and account verification to your game servers.

I just never encountered a game here with mandatory itch app usage. That is why I am curious.

Unless there is full integration ready to use for such a feature, I advise against reinventing the wheel. I assume you are single dev, so you should concentrate on your strengths and this should be in game development, not necessarily administrative tool creation. You also lose all the players that cannot or will not install the itch app.