I was a big fan of Google Inbox because of inbox zero and because of how simple it was in delivering on that. Although it was unfortunate that Inbox was killed, the features that mattered for inbox zero are now part of the Gmail app so that is my current preferred email application – both on my phone and on the web.
I think the key to a good email experience is independent of any app, and it’s based around managing what you receive. If you receive email that is not beneficial to you then that email should not make it to your inbox, whether that’s unsubscribing from newsletters, or adjusting workflows around certain tools, we should be ruthless about worthless email stealing our attention.
I think about every email as a unit of work that I will action and if I’m receiving email that I am not doing anything with then I ensure that I no longer receive them. Although sometimes I’ll have subscribed to a newsletter that maybe someday I’ll be interested in enough to justify receiving the emails, my policy is very strict: if it isn’t providing value now, it’s gone. As a consequence of this I receive very few emails (maybe 20 or so per day) and typically every single one provides value to me.
I think a lot of it ties into the hoarding mentality that a lot of people have, there’s this idea – especially in the context of technology – that we may as well keep everything since GBs are practically free and “maybe someday I’ll need that email that brand sent me in 2014 with their latest offers from that week” but there’s a hidden cost to that mentality that people implicitly take on because it’s the default.
Anyway that’s my recommendation: treat every email as if it’s someone coming over to your desk in the middle of the day asking for your attention, you’ll soon have no problem getting to inbox zero. If I were to design an email client, it would have a limit on the amount of email you’re allowed to receive and it would have limits on how you’re allowed to interact with it: no constant stream of context-stealing emails that have no place stealing attention in the middle of the day.