I don't know if fast mail provides it out of the box but I have started to test out spark: https://sparkmailapp.com/ as a replacement for Inbox. While it is a bit from as good as Inbox it can get the job done, and has bundling.
I simply set it up to archive when swiping (which is what Inbox seems to be doing). However, it's notifications are far from as good and you can't archive straight from the notification, which, to me, is a let down.
Furthermore, on iPhone 8 there is an actual loading screen when opening the app. Like, why? Everything is already stored in the phone and it should just look for new mail in the background?
So far from perfect, but what can one do when Google is killing stuff off.
One issue though: you have to be in the apple ecosystem as they do not support, anything but iOS/Mac OS.
I simply set it up to archive when swiping (which is what Inbox seems to be doing). However, it's notifications are far from as good and you can't archive straight from the notification, which, to me, is a let down.
Furthermore, on iPhone 8 there is an actual loading screen when opening the app. Like, why? Everything is already stored in the phone and it should just look for new mail in the background?
So far from perfect, but what can one do when Google is killing stuff off.
One issue though: you have to be in the apple ecosystem as they do not support, anything but iOS/Mac OS.
Note: I'm not associated with spark in any way.