I think most of this feature can be done from a web browser address bar - for example,
when I search for my username, it shows me things from my content like profile page,
posts and some private pages that were added to browser history after logging in.
You can probably find that content with the search area on a mobile device if it includes
web browser history. Also, the app/universal links idea on Android / iOS, that can
"Seamlessly link to content inside your app", could only be useful for web apps.
- Bookmarks: you can save the URL of a webpage for quick, simple access.
- Saving a webpage (e.g. “reading list”): you can download it to use offline.
There’s an idea from the original post user about this:
Maybe there could be an API for this that gets the browser to ask the user
if they would like to download the webpage to their device for offline use,
something like “discourse.wicg.io would like to save this page to your reading list”.