Life with Amazon's fitness band: Upload your half-naked pics to see how fat you'll look without exercise. You now sound stressed – relax!

AI-backed gizmo, app will predict your future body if you don't start training, analyzes your voice for unhappiness

Amazon has teased a smartphone app and wireless wristband that employ sensors and machine-learning algorithms to depict how fat you'll get unless you do some exercise - and tell you to relax if you sound stressed. All for your own good, of course....