Disclosed is an apparatus and method for automatically configuring a mobile device for collecting and inferring heart rate data of a user. The method may include capturing heart rate data for a user with a heart rate sensor that is coupled with a mobile device. The method may also include monitoring a activity state of the user from activity data captured by the mobile device, and detecting a constant activity state of the user. The method may also include inferring heart rate data for the user from the captured heart rate data during a period in which the user remains in the constant activity state. The method may also include providing the inferred heart rate data, as captured heart rate data, to a heart rate calculator during the period in which the user remains in the constant activity state.