Junto is a shared calendar with RSVPs, built for groups that need one place to see what is happening. Here is how different groups use it.
A shared calendar for a youth sports team with RSVP built in. No account, no app download for parents. Free for a small squad, one-time $4.99 for a full roster.
Plan a group trip with a shared calendar that RSVPs per activity, not per trip. See who's doing the 8am lift or the hike. Free for groups up to 8 members.