There's a new accessory available for owners of iOS devices who are looking to stay healthy and improve their tolerance to stress. While there are iOS-connected scales and blood pressure cuffs, until now nobody has looked at cardiorespiratory fitness and stress levels. That's where the new Tinké (US$99, pronounced "tink") comes into play.
The tiny sensor, available in black, blue, pink and white, uses optical sensing technologies to capture blood volume changes. With the touch of a thumb to a pair of tiny windows on the device, the Tinké app (free) calculates a pair of indexes. The Vita index is
