According to WomensHealthMagazine, April issue, the Best Wellness Apps are:
First Aid by the American Red Cross: The official American Red Cross First Aid app puts expert advice for everyday emergencies in your hand.
iTriage: No ordinary symptom checker; start with any symptom, understand the causes, get the right medical help, and book your appointment
HealthTap: Answers and tips from 35,000 US doctors
UMSkinCheck: UMSkinCheck is intended for skin cancer self exam and surveillance that allows users to complete and store a full body photographic library, track detected moles/lesions, access informational videos and literature and fill out a melanoma risk calculator