NAO becomes your personal health companion asking you if you would like to have your body mass index (BMI) or Waist to Hip ratio (WHR) calculated. NAO will ask you for your height and weight in determining your BMI. He will then say your BMI and ask if you would like to know the category your BMI falls into. Your health companion will then let you know the ideal weight range for a person of your height. If you choose to have your waist to hip ratio calculated you will need to give Nao your waist and hip measurements in inches and he will do the rest. This is a great, fun and informative app. for students, teachers, heath care workers and anyone with a NAO. It is a good idea for everyone to know their BMI and or WHR so who better to tell you than your NAO Health Companion!