Some of the app’s features — such as ones that let users undo sending, track when their emails are opened and automatically pull up a contact’s LinkedIn profile — are available in other third-party email plug-ins. But there are bells and whistles that I hadn’t seen before. Like “instant intro,” which moves the sender of an introductory email to bcc, saving you from having to manually re-enter that person’s address. Or the scheduling feature, which sees that you’re typing “next Tuesday” and automatically pulls up your calendar for that day.

These features will appeal most to power users who spend most of their day typing on a laptop or desktop. (Superhuman has a mobile app, but much of the heavy-duty functionality requires a keyboard.) Mr. Vohra said the app was targeted at people who spend three or more hours a day checking their email.

“When you’re doing three-plus hours of email every day, it’s your job,” Mr. Vohra said. “And every single other job has a tool that makes you do it faster.”

Superhuman promises to help V.I.P.s get through their inboxes twice as fast. Partly, that’s because every command has a keyboard shortcut, so a busy power broker never has to waste precious seconds reaching for the mouse. And partly it’s because the app itself is built for speed — it stores information locally in a user’s browser rather than retrieving it from Google’s servers, which cuts down on the time required to surf between emails.

I am a notoriously bad emailer. My usual Inbox Zero strategy is letting a bunch of important emails pile up in my inbox for months, before going on a guilt-driven purge in which every message I send begins with “Sorry for the delay.”

But with Superhuman, I bushwhacked through my unread emails in less than an hour, eventually reaching a kind of dissociative flow state. Invitation to a blockchain-themed happy hour? Hit ⌘-; to insert a “snippet,” a canned reply politely declining. Newsletter from a hotel I stayed at once in 2014? Hit ⌘-U to unsubscribe. It made checking my email feel less like doing work and more like speed-running a video game in which the object is to annoy as few people as possible.

It’s strange, on one level, to think about my email at all. For years, email felt like a remnant of an earlier technological era that was fading into obsolescence. Workplace chat apps like Slack sold themselves to large corporations as “email killers,” and messaging apps replaced email as many people’s primary inboxes.