When Does a Smartphone Become a Medical Device?

The issue of regulation has huge implications for innovation in this space. 
Part of the transformation of health care is the new technology that allows smartphones to be used for diagnosis and tracking medical concerns. These mobile apps do everything from monitoring heart beats to managing glucose levels. There were more than 7,000 health-related apps for the iPhone in September 2010 according to a MobiHealthNews study. With the popularity of the iPad these numbers are sure to grow.
However, it’s important to realize that any programmer can develop a health app. Apple puts the responsibility of following regulatory guidance on developers. So when do these apps (and the smartphone or tablet itself) become considered medical devices requiring monitoring by the U.S. Food and Drug Administration (FDA)?