The bell-shaped icon present on the top right corner displays in-app notifications. Currently, in-app notifications display the following: Customer activities in customer portal You will be notified whenever your customers: Views a quote/invoice/retainer invoice Comments on a quote/invoice/retainer invoice Accepts/declines a quote Pays for an invoice or a retainer invoice Feature announcements You will be notified whenever we launch a new feature in Zoho Books. The What’s New section, which features every month, notifies you of all the latest updates and additions made to the Zoho Books application.