Mailbox had multiple causes of death. Most people don’t download email apps; those who do don’t want to pay for them. The only path forward for an email app is acquisition, and the fate of most acquired apps is death. Other email apps copied Mailbox’s best features; aside from a somewhat dubious automatic archiving feature, Mailbox stopped building... See more

The market for consumer productivity apps, which spurred companies like Dropbox and Evernote to multi-billion-dollar valuations, has proven to be mostly a mirage. Businesses are increasingly happy to buy software for their employees; people are often loath to buy software for themselves. And for all it did right, Mailbox never became anything more... See more

Email apps are good at being better. They've invented or popularized some of the most innovative ideas in software—even if they can’t always find a business model to match. And those features are what live on.