User-private annotations on the map

I think the ability to archive igm's and notifications in folders would take care of this note feature.  A menu item would then allow a popup showing saved messages or notifications.  Messages might be too much but archived notifications would be good!

It would also be good to be able to mark a note to expire after a certain time, e.g. to mark a note about animal parts to expire after a week. This would save the need to go round deleting all the stale old notes.

I agree with this . 

I scout the spots I harvest (especially for animal remains) and keep notes of what's (to the best of my knowledge) on each spot, revised to reflect my harvesting and re-scouted when notifications contradict notes.

It would be really nice if this were integrated into the game so that, when I click on a tile to get the menu (view centred, send units, etc.) that shows what's on the tile, I also have the option of adding notes to that tile, that shall be displayed on that menu in future, until I delete each note. Display as a short title and support expanding inline, like the harvesting sub-form, would be a nice arrangement.

I'd also want to be able to edit such notes and, potentially, have several such notes on one tile (e.g. a persistent note for the rare herbs there plus a transient note for the animal remains from when I cleared the spot so my herbalists could resume harvesting). I could live with one note (adding details and removing them) but having several would mean I could delete one of them when it ceased being relevant (the animal bits are gone), a more atomic action than editing. For bonus marks, I'd like to be able to tell an IGM from a scouting mail to turn itself into a note on the scouted tile, but I can always do that by hand.

This way, I'd be able to see that the spot still (probably) has 26 wild dog furs on it after I've harvested what else was there, as part of the display I see when I click on the tile to decide whether to send harvesters. It'd be my note, so any inaccuracies are my responsibility; I'd update it when my harvesters come home with part of the heap and it'd get out of date if anyone else harvests there, or when part of the heap times out; those are proper limitations and I'd need to re-scout to get definite information.
I'd cease needing to keep all of this information in an external place; and I'd have my notes when travelling with my tablet, on which I don't have the same easy ways to make notes as on my desktop (which lets me have two applications open side-by-side, unlike the tablet), even if I were to sync the notes between them.

Having the ability to share a note with my alliance, or with specific other players (e.g. a neighbour with whom I'm co-operating to share the harvesting), maybe even make a note public, would be a nice bonus; but would require some hard thought in the design to avoid spam/clutter and kindred inconveniences (and configuring of privileges: read, write, delete, share onwards, ...). Conversely, it is important that there be no hint to other players that anyone (but them) even has a note on a tile, aside from their own and any shared with them.

It would also be nice if the drop-down menu on a map tile showed the tile's distance from my currently-selected city, so that I can work out how long it'll take harvesters to get there (without having to use an external application to work it out); better yet, show the travel times for harvesters on the sub-menu for that (and for diplomats in the page for their orders, as in the Send Army page). This might also mitigate the problem of inadvertently sending harvesters half way round the planet (with no grace period in which to recall them) if I forget to switch cities !