The Reminders app in iOS 5 can be very handy for creating quick and simple task lists or reminders without having to resort to third-party apps, and with Mountain Lion these Reminders can be easily synced via iCloud and managed on your Mac as well. Unfortunately, its flexibility for repeating reminders is somewhat limited, at least on the surface. Users are given a choice of only five repeat intervals: Every Day, Every Week, Every 2 Weeks, Every Month or Every Year, and the Reminders app in OS X Mountain Lion isn’t any better in this regard. Fortunately, for iPhone 4S users looking for a bit more flexibility, Siri comes to the rescue by allowing custom intervals to be created using your voice; simply tell Siri something like “Remind me to take the garbage out every three days” and it will happily offer to create a Reminder with the specified repeat interval. The resulting task can even be edited in the Reminders app to adjust things like dates and times—as long as you don’t change the custom repeat setting, Reminders will leave it in place and continue to repeat your completed task at the specified interval.
For more information and some other options for setting custom repeat intervals, be sure to check out our Ask iLounge article on Setting Custom Repeat Intervals in the Reminders app.