Can I wear the exerspy armband on my right arm? Or upside down?

Answer: Algorithms analyze the armband data to estimate your calorie burn. Those algorithms have been written to give optimal performance when the armband is worn on the left arm, the right way up. The "right way up" has the logo closer to your shoulder and the lights closer to your elbow. We do not recommend wearing it on the right arm or upside down. If the armband is worn on the right arm or upside down we expect calorie burn values may show a difference of up to 8% for routine activities like resting, walking, running, household work, and road biking. The differences can be significant when using certain exercise equipment. The armband should NEVER be worn on the leg.