I need to organize child care by multiple parties for months at a time. The days/hours/and schedules vary greatly from week to week. We mostly have iPhones and iPads now. I just started the free version of Cozi for myself, but it doesn't seem to work well and I am not happy with it. I'm thinking google calendar may be the best bet, but my "shareable calendar app" searches aren't turning up much useful info for me, so I figured I'd ask the experts: What shareable calendar apps do you find most useful for multiple parties to access and edit?