iOS: Apple's Reminders is an OK app, but its location-based reminders aren't particularly quick to create. Checkmark is much better, making it a snap to create reminders at any spot, and it's free today (down from $5.49).
We've talked about Checkmark quite a few times, and it really is a great app. You simply set your favourite locations and can create reminders for them in just a few taps, much faster than Apple's default Reminders app. You can also set time-based reminders, snooze them, and much more. Hit the link below to grab it for free.