Reminders is a component of iOS and OS X that allows users to set notifications for themselves and create lists.[1] It was a new feature in iOS 5 and OS X 10.8 "Mountain Lion". It can sync data between iOS and OS X through iCloud.[2]
Features
The Reminders app can have multiple user-created lists of reminders. Reminders appear in the Notification Center 24 hours before the time a reminder is set for. Each reminder has a title and can be marked as completed (checked), and is automatically hidden. Additionally, each reminder can optionally have the following:
A priority, from "Low" to "High"
A note about the reminder
An alarm at a certain date and time. If a time-based alert is set, it can repeat every day, week, two weeks, month, or year.
An alarm when a geofence around an area is crossed ("when I leave the conference" or "when I get home")