Wearable Sensors and Clinical Trials by Google & Co.
For a dynamic site with reviews and recommendations for apps for use by doctors:
Best fitness gadgets of 2017, a review by a Forbes contributor:
For an incredibly comprehensive database of wearables including medical devices, see:
For information on a brilliant, award-winning lifestyle app: TickerFit™, a unique personalised programme delivered using un-intrusive mobile and web based technologies:
The Alivecor or Kardia works with iphone and some android phones. It costs around €120. It is a fully validated medical device.
Activity/Sleep, Heart Rate, Temperature, Blood Pressure, Weight, Body Fat
Nokia, the Finnish company famous for mobile communications, now has a very smart range of reasonably priced medical devices for home use: