I’m not using (and probably never will) any of the non-email features like the calendar, or the chat. But they are relatively hidden away, so they don’t bother me.
But indeed if you don't use it it does not get in the way, which is perfect.
Of course I keep them there when I download in K9.
The difference is that with the third-party approach, the third party is really a risk factor of unknown magnitude (even if trusted and paid). With the "local" approach you are in full control.
When I'm working I always have access to my laptop with the complete mail archive.
When I'm not working I don't need the mail archive. Access to the latest mail in the POP3 server is enough. Proof is all these years since 1994. Furthermore I didn't have any access to my mail when away from my computer up to my first Android phone in 2011. Nothing bad happened to me and to the vast majority of people, which were handling mail in the same way pre smartphones. I mean: no access when on the move.
BTW, when I send mail from the phone I BCC myself so I'll download the message for permanent storage later on.
I'm curious as to why, if you don't mind! Are you specifically looking for "download only once then get rid of it"?
My mail stays on my computer, backed up locally and encrypted to a remote location.
I lose the ability to access old messages from remote but it never was a problem in almost 17 years of self employment. Before that, I already had about 13 years of downloaded emails, from the times when web mail was not a thing. No need to upload my old messages to Gmail, if this is even possible. I just kept using a local mail client. For my personal mail I remember some emacs clients, Netscape Mail (bundled with the browser,) Outlook Explorer then Thunderbird. I might forget something.
But after I started running my own server, I prefer IMAP so that all of my email is in one place regardless of what machine I'm using. And it still lives on a machine that I have control over.
Same here. I want to "receive" each message exactly once, not have it synced automatically all over the place. I only handle my email from either my desktop computer or my laptop, with a simple script to copy it all back and forth whenever I switch the device I am using.
I was on call for my jobs for decades and never had any problems with this method, however it was before smartphones became common. I do not handle email on my smartphone, ever.
It’s perfectly feasible to write an email client that hands off received events to a calendar application and receives the response to send back. It’s all icalendar components under the hood anyway.
Putting everything together in a single monolithic program that handles email, calendar and contacts is a design choice, not a technical requirement.
And yes, I do use the workflow that your descube receiving and sending calendar events. But Thunderbird’s design is annoying because it’s a all or nothing situation: you can’t just use it as an email client and use some other calendar application.