It would have to be rewritten from scratch. I already built a damus web app, which was forked to https://yosup.app . I stopped working on it due to continuous security issues on the web. You can do a PWA that is still native which i am working on now, but its a lot more work.
Is it possible to turn the Damus iOS app into a web site that we use ? Like Twitter.com … Instagram … Hive.blog, Steemit.com … Blurt.blog … maybe we earn Damus “Zap” that we can convert to Bitcoin on Ionomy.com … No Apple Store App required …. https://Blurt.blog #[1] #[2] #[3] … 
Discussion
What do you think of Iris.to ? Web based…. No Apple IOS app required
Pretty easy to set up. And get your profile name …. https://iris.to/offgrid