|Image via Avocado.io|
You can each create events (i.e. Holiday Party on 12/22/12, Doc Appt 1/15/13) and even set up reminders to alert both (or one) of you when an event is coming up. The best part is that anyone couple who downloads the app before January 1st, 2013 will automatically be upgraded to their Unlimited account--anyone couple who downloads Jan 1st and after will be charged $19.99/year.
It's a great app for private communication--I highly recommend d/ling it before the new year so you guys can get it for free. Enjoy!