Researchers at the University of Washington in Seattle and Intel have created two new cell phone applications -- UbiFit and UbiGreen -- to automatically track workouts and green transportation.

The programs display motivational pictures on the phone's background screen that change the more the user works out or uses eco-friendly means of transportation, researchers said.

Sunny Consolvo, a recently graduated University of Washington Information School doctoral student and one of UbiFit's creators, said that in a 3-month field experiment, people using UbiFit with the background display kept up their workout routines over the winter holidays.

Current versions of UbiFit and UbiGreen use an external sensing device -- the Intel Mobile Sensing Platform -- clipped to the user's waist. The device includes an accelerometer -- a device that measures acceleration -- to sense the user's movement.

The programs could run on phones with built-in accelerometers, such as the iPhone and the new Android G1, with no need for external equipment, the researchers said.