Add link to Nextcloud web version in app

I want to reference to the ticket on the android version first
https://github.com/nextcloud/android/issues/356

And quote my response from there, because it sums up the idea

I have given my family a Nextcloud and looking at the parents working with it I figured out they are overwhelmed and unable to understand why they need a Nextcloud app and a browser and remember URLs or find bookmarks.
It would be therefor great to have the app, login in there and than the Nextcloud app lets you open the browser directly from within the app or even better, opens a browser WITHIN the app (like feed readers are doing).
My idea would have been to have the same "apps" being shown in the Nextcloud app. In my case would be contacts, calendar, mail and files. The all work great already with the mobile view on a mobile device but it is just not seamless for people to get there. A click on an icon an the web version opens, would be great.
This would allow to have Nextcloud #as THE SINGLE app to get access to everything. Files natively supported, everything else not yet "natively" implemented in the browser (within or external app).

Start by reading the linked Android issue and the quoted proposal in this issue to clarify the intended scope. The work is complete when the iOS app provides a straightforward way to open the Nextcloud web version, either within the app or through the browser, with the supported web apps represented as intended.