Simple Calendar - A simple calendar with events (optional recurring and reminders), week numbers and a customizable...
Webmobi - Create mobile apps for Events, Festivals, Enterprises & University Campuses with webMOBI Mobile App Builder | Start Building Free!
Etar - Material design open source calendar for Android.
Calendify - Calendify is an event community where you can share, publish, and subscribe to event calendars. It helps you to stay informed about what you are interested in and what is yet to come.
Google Calendar - Spend less time managing your day & more time enjoying it
Apple Mail - There’s big news attached.