How will Shortwave build a profitable email management business independently, despite similar products (e.g. Mailbox, Sunrise) being unsustainable?

All of those products were definitely an inspiration for us. A lot of those brought new innovative product designs and features to their apps. Mailbox brought swipe actions. Inbox by Gmail brought bundles. All of these features are an inspiration for us to continue to push the boundaries on the innovation we can do on the product side.

They also showed us that the business fundamentals are really important. All of those tools had good single-player consumer experiences, but they didn't really have a path toward actually getting people to pay for them and serve real business use cases.

You can look at the calendar app Cron as another example of this—a company that is taking an app and trying to think about the business use cases up front and make sure that you have customers who are going to be relying on your tool to do their job and therefore will pay you in order to support all of the users we want longer term, who maybe are using it more for personal use cases and the pricing is too much for them to pay.