Example disposable biosensor devices having an activity sensor are disclosed. One example device includes a disposable biosensor that has a first electrode having a distal end to be inserted into a subcutaneous layer beneath a person's skin, the first electrode having a reactive material disposed on the distal end, and a second electrode. The disposable biosensor device also includes an activity sensor that can be activated upon an activity by the person, the activity sensor for detecting the activity and providing data about the activity. The disposable biosensor also includes a radio frequency transmitter for transmitting data obtained from the first or second electrode and the activity sensor.
