Two kinds of notification, two places to set them
Zite can tell you about your work in two ways: in-app notifications - the bell at the top right on the web and the bell on the phone - and email. Both are personal preferences; you set them for yourself, and they apply across all your projects.
What you are notified about is set under your avatar → Settings (the NOTIFICATIONS page).
Whether you also get those notifications by email is set under your avatar → Edit Profile → EMAIL.
The pages that follow cover each in turn, then the same settings on the phone.