Keeping a medical diary sucks. We're building something better: An app that periodically asks you questions about your lifestyle and symptoms, and learns to cater its questions and suggestions just for you.

We're aiming to tackle all kinds of chronic medical conditions, starting with migraines. Please register here if you are interested: http://dintu.com

I think you need a bit more here then just headaches to start with. Seems like you could broaden your initial offering to include other medical maladies that require logging.

My dad needed to start tracking his blood pressure / heart rate / glucose levels at multiple times of day and having a text that acted as a reminder and a reply that acted as a log with the data would've been perfect for him.

Is the number of people that need to log this other information > or < than the number of people that want to track headache triggers. I've honestly never met someone that wanted to track headache triggers but know a lot of people that need to track other medical issues.

Maybe people with those other medical issues tend to be older than the target audience for an iPhone app?

I really like this, too. I have a stomach problem that took years to figure out -- would have been very helpful to this kind of tool.

personally I wouldn't use this but I think its a great idea. that being said i think allergies might be a larger market than migraines.

+1 for wanting to use it for figuring out food sensitivities.