Hey jgert,
QuickBooks Online is focused on helping you earn profits while simplifying your bookkeeping. Online delivery of invoices ensures you'll always give your customers access to the most recent version, and comes with additional tracking benefits. When you send your customer an invoice, they receive a detailed email with a link to the online version. Since it isn't always possible to receive read receipts for emails, invoices appear as viewed once your customer clicks on the link. Currently, the easiest way to see this status is from the Invoices section of your Sales tab.
If you'd like us to tweak this feature a bit further, you can help shape the future of QuickBooks by submitting feedback directly to our engineers. Your comments play an important role in guiding our development efforts.
Hope this helps! Don't be afraid to submit your feedback. Together we can keep elevating the QuickBooks Online experience to new heights.
