Why are reminders device specific?

[eusty]

I set a reminder for the next day on my SP3 and I expected my phone (930 WP8.1.1) would remind me, but it didn't! When I got home and opened the SP3 it reminded me!

What is the point of a cloud based assistant if it can't communicate to other devices!

 

[eusty]

OK it's an 8.1 issue.

When I check on a phone running WP8.1 I can only see reminders which have been set on that phone when I look at the history. If I check a phone running WM10 then the history is the same as on the W10 PC.

 

[xandros9]

Interestingly enough, I set a Cortana reminder on my Lumia (I forgot whether it was WP 8.1 or 10) and much to my surprise my iPhone reminded me - the Reminders app had hooked into my Outlook account and it seems it syncs.

 

[anon(8555314)]

My two W10 devices (W10 SP2 and 950XL) communicate Cortana reminders with each other, but my W8.1 Lumia 1020 is an island.

 

[Rezelius]

Is there a setting that would stop the Reminders from syncing between devices? I looked but couldn't find anything.
Yesterday morning I set a reminder (using Cortana) on my Desktop PC running Windows10 yet my phone (Lumia 635 running Win10 Insider) did not display the reminder at all throughout the day, however when I got home that night, the reminder popped up on my Desktop. The reverse is true as well: set a reminder on my phone and it does not show up on my desktop. Seems odd.