Sometimes it is just easier for co-parents to communicate online with messages and visitation schedules so they don’t get distracted and drawn into arguments.
I have seen a few websites devoted to this idea, with visitation calendars and other features for a fee.
But today I ran across Cozi which says it is a site for organizing your family life. It is completely free, totally user-friendly, and has a color coded family calendar, photo upload, list maker, email, journal and more. I signed up and was able to use it in about five minutes. While probably designed for the intact family, it occurs to me that this is a perfect tool for visitation schedules and messages.