It’s an interesting exercise, but I feel this is actually going against one of the principle rules of UX: you want the user to be able to perform the primary actions of the app in as few clicks/gestures as possible. A single email per screen may decrease cognitive load, but it increases physical interaction. Now, instead of being able to quickly glance over 10 emails and do a simple flick to scroll to see more, I have to do at least 10 swipes to digest the same amount of information.

The real problem with email is that there’s too many of them. The primary use of an email app is to be able to sift through the junk to get to what’s important, quickly. A list view is the best we have so far, but I agree with you it could be improved.

Perhaps you alter your concept to use a scrolling card interface, where you at least show 2–3 emails per screen, but you can perform the same swipe gestures to archive/remind. This makes the interaction model a trinary model instead of the Tinder-style binary model: there are three possible actions now:

• Remind (swipe left)
• Archive (swipe right)
• Skip/ignore till later (no action — just scroll past it)

I’d argue that the addition of the “Skip” action reduces cognitive load even more, since if you quickly glance at it and aren’t sure what to do with it, you just keep going. It doesn’t require an extra conscious step to ignore it.

Then, once you’ve gone through the initial “filtering” step, you could click over to your “Remind/TODO” list, which would present the emails one at a time in your swipe-style design. This list is the emails that you know you have to get through, so having to deal with them one at a time seems like a good use case for your design. Thanks for the writeup!