There are a number of applications that allow you to create to do lists, tasks, set up reminders but none that have all the functionality to be really useful. The reminder application in iOS 5 has some cool features such as location based reminders. There are applications which notify you when your friends are close by. But there is no one application which rules them all.
These are the unique features that I can think of in addition to typical ones in most apps:
- Remind me to do something when a friend is within certain distance from me (want to talk about something with a friend but no worth sending an email). I have some ideas on how to ensure privacy issues related to tracking friends.
- Allow tagging appointments with location, remind me of an appointment if I am moving away from the location within a certain (going out for lunch, may be I forgot about the meeting)
- Remind earlier if I am not at the location (out for a long lunch and forgot about the meeting, the 15 min reminder may be too late)
- Allow specifying a set of locations or stores for a to do list (groceries from safeway, nob hill, albersons, only close to home, not when I am at lunch from work), if the list is not empty and if I am within a certain distance from one of these locations, remind me.
- Good set of snooze options (do not remind me again today, this week, this month, etc)