Tab in browser provides way better user experience than electron app (or native android/ios app). With website you can to mind-blowing things like:

* Open other part of your app in new tab.

* Open other part of your app in new widow, and have time side by side.

* Open external link in new tab, in the same window (OMG!!!).

* I can send link from the web app to someone else.

* Consistent back button.

* Use browser extensions.

* Have cookies (i.e. I am logged out of most of the things in your in-app browser).

Composers are generally thing that are better in apps, but as long as I don't need to compose complex stuff, web app always wins. And if I do, I'll prefer to use native/electron app only for composing, not for consumption.