Wahoo Fitness has introduced two new fitness sensors: The Fisica Fitness Sensor Key, and the Fisica Fitness Sensor Case. They fit into the same connector port used for docking and charging your device. Both are Apple certified, so they aren't just obscure little devices like the J8 iClone.
They support ANT+ sensors, and can receive transmitted data from weight scales, power meters, blood pressure monitors and others equipped with the tech. They also have "many apps in development with partners" as well as a "free App at launch that will act as a really nice cycling or running computer and offer the ability to save and upload of email your data to the service of your choice."
The Sensor Key runs about $80, and is available now, and the case can be pre-ordered and ships November 1st.