Startup Idea: Shared Shift Management Mobile App

Startup idea to develop a convenient mobile app that allows shift workers to input, monitor, and modify their schedules. Users should be able to share their account and schedule to effortlessly sync up with the shifts of fellow shift workers.

I am looking for a good, easy to use app that would allow me to input my husband's master schedule (think shiftworker) and add in my monthly work schedule. Ideally we could both access schedule and modify it from our own phones. It is very difficult to track two shift workers schedules. And there is nothing that offers the added feature to share an account/calendar.