What are you asking for, here?
Discord has a “Discord” app that lets you sign up for any number of Discord channels in the app. Discourse has the same thing for iOS, the “Discourse Hub,” that lets you sign up for any number of Discourse forums.
Are you complaining about Discourse Hub’s quality? Ease of use? (Do you have bugs to report?)
Or are you complaining that there’s no Discourse Hub for Android? (Why would you want one? On Android, the website itself can send push notifications.)