Yes, there are options, like the one I use currently or the Todo folder you suggested. I suppose like everything else it's a question of gradual improvement.
Re the mechanism, I'm not a coder, but can visualise a few options from the user side.
Option A (Reminder notifications)
1. There is a Snooze button option when you swipe a message in the message list. Also on the message toolbar or the message view menu.
2. On tapping, a new dialog comes up. Has presets like, 15 min, 40 min, 1 hour, tomorrow, as well as option for custom time.
3. On choosing one, the email id, time at which to remind, subject etc is stored somewhere in a local database. The time at which reminder is to come goes wherever reminders go. (do remember this is non coder talk
)
4. At the reminder time, there is a rich notification in the notification are. Title can be "Snooze alarm for email <from> on <subject>" or something. One button for View mail, one for Snooze again.
Option B: (Use version of share to calendar)
1 Bring a copy of Share to Calendar button to the main menu or the swipe menu
2. Call it Snooze (or whatever)
3. On tapping, it again shows the dialog asking for period,
4 After selection, it does 2 things. First, make a virtual copy in a virtual Snooze folder (like Smart folder) then automatically creates a calendar or task entry with reminder notification for that time.
4 The rest is taken care of by calendar / task app
5 Not as friendly to use as Option A, but might be easier to code since most of it is already there.
Anyway, this is an intellectual exercise on how to do it. Whether and when to do it is always up to the developer, and right now the big thing is the contacts sync.
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