One of the most forehead-slappingly clever iPhone app ideas I've heard is iNap, an alarm clock for public transportation commuters to wake them up when they get close to their intended stop. Rather than setting a timer, you set the location of your stop on a map and then your iPhone 3G follows your location and the alarm goes off when you are within a specified range of your target. As someone who has spent several years going drowsily to work on public transportation, I applaud the developers of iNap.
The other day, I was driving home to pick up my wife to go somewhere, and, as I approached our neighborhood, I wanted to call her with my mobile phone to tell her to come down from our apartment and out to the street so I wouldn't have to park. But there were a few round-a-bouts to negotiate and I didn't feel comfortable using my cell phone while I was driving (it is actually illegal in Spain), so I ended up parking and going up to the apartment to get her.
Okay, here's my idea: I want an iPhone app that:
When I get within a specified radius of a geographic point, the app will initiate a phone call to someone, play a recorded message (e.g. "Hey honey, I'm 10 miles away. Be there in 15 minutes!"), and hang up.
It can be called "Almost There!" or "Honey, I'm almost home!" or "Hot Meal".
Favorite Sites - You would be able to save several "favorite" geographical destinations (e.g. Home, Work, Grandma's House, etc.) and reuse them quickly without having to launch Google Maps. Of course my contacts' addresses should be available as well. Active Time Window - It should also have an optional time of day and day of week when the trigger should be active. If my work takes me to a client site that is near my house, I don't want it calling my wife to tell her I'm almost home from work for the day. Missed Call - It might also be nice to avoid the recorded message and have it call a number, let it ring once, and hang up. This old "no charge communication" trick has been used by penny pinching phone users for decades. If your recipient has been briefed on what a missed call from you means at a certain time of the day, why go through the trouble of playing a recording?
As someone who often prepares lunch for my wife when she gets home from work, I find it really helpful when she can give me a ring to say she's leaving work and will be home in 15 minutes. When she does that, the meal is always on the table and piping hot when she walks in the door. Advising loved ones who are preparing food for you seems like the most useful application of this iPhone app, but I suppose that calling your office assistant or friends would be helpful too. It sure seems like quite a few people would pay $4.99 for such an app.
I have no iPhone API experience and no free time to learn it. This idea is quite complex and uses four main interfaces of the iPhone API: maps, call initiation, audio recording, and GPS. It's not a good starter app; it requires an experienced developer. Also, I have no idea if you can even play an audio file into an initiated call or not. If someone wants to write this, great. If it's already written, by all means, let me know and I'll buy it.