I know that folks tend to have strong feelings about the iPhone (I love mine...it completes me :-) ) and understand that as far as phone applications go, well, to each his own. So please think of this post less as an endorsement of the iPhone, or even this particular application, but as yet another instance of excellent matching of function to technology.
This is the "Pocket First Aid & CPR Guide" from Jive Media LLC. It's an instant first-aid reference always with you on your phone, with additional screens for your own emergency medical information (link to your Dr.'s office, your emergency contacts, your preferred hospital, your allergies). AND: the first-aid instructions are available even when you are out of cellphone range. Reviewers at the iPhone app store are asking for the addition of emergency phone links even when out of country, and for pet first aid info, so I would imagine that, and more, will be added soon. $1.99 US.