https://www.gamespot.com/articles/destiny-app-update-adds-new-features-removes-suppo/1100-6453016/

With Destiny 2's release coming up very soon, Bungie has now updated the Destiny Companion app with some new features and also removed support for the first game.In the new version of Destiny app, there are five major areas:

Bungie's own website has been overhauled as well, and you can use the site to track some of the same things. However, Bungie made the decision to "double down" on the Destiny companion app, so that's where you can expect the newest content.