Users submit timestamped exposures to possible irritants or other possibly problematic activities, and also timestamped medical symptoms, either real-time or backdated (or planned). Each item can be tagged and charted. Tagged exposures can be charted with tagged symptoms. This is not intended to diagnose anything, and is no substitute for a medical professional looking over this, but it may be a valuable diagnostic aid.
As such, all user accounts are by default protected, although invitations to view data may be issued. Data may be made public by the user, in whole or in part.
Inspired by my friend who uses a locked-down, friendless Twitter to track food consumption, and my subsequent recommendation of same to another friend who wants to track IBS symptoms against foods, but has no attention span. I was thinking in the shower that this would be even more useful with some basic calendar and analytic functions.