Location-based alerts in the iOS Reminders app are great for letting you know to do something when you get to or leave a specific place, and now iOS 7 makes them even more useful by letting you manually set the distance at which you want to be alerted.
When setting a location-based reminder, a map will appear with your selected location, along with a circle representing how far away from the selected location that the reminder will be triggered—often referred to as a “geofence.” You can hold a finger on the dot at the edge of the circle to adjust this radius from as little as 100m up to around 2,400 km.
The shading of the circle also illustrates whether your reminder is for arrival or departure, with the blue shading effectively representing the zone in which the alert will be triggered.
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