Twitter and Universal Links
Available for devices running iOS 9, Universal Links are regular HTTP links that, when tapped, will open the relevant view in a native app instead, with an option to view in Safari. Universal Links are safe, shared across platforms, and they can only be enabled by apps that have associated websites.
[…]
As I noted in my iOS 9 review, third-party Twitter clients won’t be able to take advantage of this integration as only associated app domains (in this case, twitter.com) can verify their iOS app. Even if you don’t use Twitter’s app for iOS, I would recommend keeping it installed if only for the better experience of automatically opening Twitter links from Messages, Mail, and other apps in the native client instead of the website.
Disappointed with Apple’s implementation of Universal Links. IMO should be fully client based and let users choose which apps to open.
Update (2015-09-22): Apple engineer Jonathan Grynspan suggests that Twitter could support third-party clients via the apple-app-site-association file. Based on my understanding of how universal links work, this would not be a good solution (and I doubt Twitter would do this, anyway). But I may be missing something. He refers questions about this to Jonathan Davis.
Twitter is the authoritative owner of their links. If they want to allow third-party apps, it’s up to them.
App ordering in the JSON file is respected when using arrays, so (if a site wants) they could prioritize third-party clients.
