We've decentralized the "Add New" button to provide more context for when to use each type of document. This also helps with creating notes in specific groups (and will apply to tasks when we roll our Group Work in Phase 4).
You can create new documents by clicking the "+" button on each item of the sidebar.
Each screen in the app also has a button in the top right corner for creating new documents. For example: "+ Note", "+ Wiki Page", "+ View", etc