My toes are tingly, my head kinda hurts, and last night's a bit fuzzy. Did I have a seizure? Is it lupus? Where's my iPad? The WebMD app will help me figure it out—Oh God! It's Sjögren's syndrome!
I'm not sure how accurate the diagnosis you'll get from the WebMD app might be, but it's certainly a decent reference. There are symptom descriptions, drug and treatment information, local health listings, and a great section of first aid pointers.
While not a substitute for a visit to your doctor, the WebMD app is clean, well organized, and easy to navigate—actually, I think it's even easier to navigate than the regular WebMD website.
The app's free and available through iTunes right now. [iTunes]