Flexible electronics have significant potential for applications in medical devices. Still mostly in the developmental stages, I believe it will be very soon that we will see them in commercial products.
According to an article in Medical Design Technology, a team at the University of Texas at Austin has developed a way to manufacture flexible electronics that is much faster than current methods. The availability of quick, low-cost manufacturing methods will encourage companies to speed up product development to be one of the first entrants in a potentially huge market.
Flexible electronics with integral sensors could be made into all sorts of wearable devices. Because they are basically just thin, flat patches that conform to the skin and move with it, signal integrity should be much higher than that of current devices that are mostly in the form of wrist bands. I can envision very inexpensive monitoring patches that are specialized for particular uses, and could even be once-and-done disposables.