In my review of the iPhone 4S, I talked a bit about location-based reminders. Particularly, I brought up some use cases that I think could come in very handy for a family.

In Anna’s and my near-seven years of marriage, I don’t know how many times one of us has swung by the store without the other knowing it and then, upon returning home with some groceries in hand, the other says: “Oh! I wish I had known you were going to the store. We’re just out of [some item].”

And so, one thing that would be useful for setting a location-based reminder is if it could be shared. I wrote:

An example of that in real life could look like this: I’m at home and realize we need batteries. I create the reminder and it syncs to my iPhone and Anna’s. Then, suppose Anna realizes she needs to swing by the store on her way home from work to get an ingredient for dinner. When she gets there a reminder pops up notifying her that we also need batteries.

Come to find out, as Brad McCarty pointed out at The Next Web, shared lists in Reminders app are doable using iCloud. They can only be shared via the iCloud website.

To share a Reminder list, log in to your account on icloud.com, go to the Calendars app, click the round satellite/wi-fi radio beams-looking button that is next to the name of the Reminders list which you want to share (or create a new one for sharing), and then enter the email address of the person (or persons) you wish to share that list with.

The new list will then show up in your Reminders app, and once the person you’re sharing it with accepts the invitation, it will show up in their Reminders app as well. I created a list called “Shared”, that is synced on my iPhone as well as my wife’s. Any reminder I or she creates or checks off on that list will be synced on both of our iPhones.

Now we can share any type of Reminder that the iPhone supports: regular, time-based, and location based.

For shared location-based reminders, it’s important that both people have the same contact names and addresses for certain locations such as Walmart, work, home, the grocery store, etc. Also worth noting is that if I set a shared reminder to check the mail when one of us gets home, the alert will go off on both of our phones as soon as either one of us triggers the reminder, even if the other is still out and about.

So now I have two reminder lists on my iPhone: Reminders (which is my main list), and Shared (the one that Anna and I have synced). By default, Siri creates new reminders in your iPhone’s default list. You can change what the default list is in Settings → Mail, Contacts, Calendar → Default List.

I am keeping my own Reminders list as my default list because that’s the one I use most often with Siri. However, I still want to use Siri to add shared reminders on the synced list that Anna and I both have.

Unfortunately, getting Siri to add a reminder to a specific list other than the default list can be tricky. I for one have had quite a difficult time with it.

For example, the following Siri commands in which I am trying to create a reminder on my shared list (which is called “Shared”) all create a task on my default “Reminders” list:

• “Create a shared reminder to take out the trash when I get home.”
• “Create a reminder on the shared list to take out the trash.”
• “Remind me to take out the trash when I get home on the shared list.”

If I ask Siri to “Create a shared list reminder to take out the trash”, Siri will tell me that it cannot create lists.

But, I have found one path of syntax that works. And you have to be pretty specific with it too:

Me: Remind me to take out the trash when I get home.

Siri: Here’s your reminder. Shall I create it?

Me: Move it to the Shared list.

Siri: Okay. I can add this to your Shared List in Reminders. Shall I go ahead?

Me: Yes.

Siri: Okay. I’ll remind you.

Moreover, it seems that only the phrase “Move it to the [name of other list] list.” will work. If I say “Put it on the shared list” or “change it to the shared list” Siri will not move it. In fact, Siri will change the content of the reminder to “On the Shared List”. Oy.

So, in short, adding reminders to shared lists with Siri does work, but it could use a bit of polish.