D-shirt of Smart Sensing Technologie by Cityzen Sciences. Through the shirt's sensor-laced fabric connected to a bluetooth transmitter, your activity can be tracked while you move, and it's sent to your smartphone. The material can be washed and ironed (though the transmitter must be removed first) and it is no heavier than a regular t-shirt.
For the launch of the brand, Smart Sensing will showcase their potential with mass-market sports products: a t-shirt and cycling bib tights sensing directly the wearer’s heart rate, GPS location, speed, etc. These clothes, equipped with an artificial intelligence adaptable to each sportsperson, will be commercialised with personalised real-time coaching and monitoring applications.
The company hasn't released a prototype yet, but they did talk about the exciting product at CES 2014.