A method includes receiving one or more messages including a first message from a first mobile device. The first mobile device is wearable. Based at least in part on the first message, the first mobile device is associated with a first user. Steering wheel movement data during a first time period and movement data from the first mobile device during the first time period are also received. Based on the steering wheel movement data and the first mobile device movement data, it is determined that the first user occupies a vehicle driver seat.