As is the case every year, there are a whole bunch of new features included, and the first developer beta was made available after the keynote.
Some of the biggest changes include a new UI, with home screen widgets and an app library.
Moreover, you can finally have certain apps only appear in the App Library, as opposed to the home screen.
You can now pin various chats to the top of the app, and there are new group photos to reflect who is in a conversation.
Pinned chats will see speech bubbles appear when someone messages you, and of course, there are new Memoji effects.