Joseph Jose never leaves home without his activity tracker. He says the results have been eye-opening! Joseph Jose "What I found out is that I was actually moving a lot less than I thought I was." An activity tracker uses sensors to gather information about the steps you take and the calories you burn. Joseph's tracker syncs to his phone or computer when he's ready to crunch the numbers. But are activity trackers accurate? In Consumer Reports' labs, a panel of volunteers wore them on wrists … arms … and clothing to find out. The panelists walked on a treadmill … used an elliptical exerciser … climbed the stairs … and picked up toys, crossing the room to toss them in a bucket. Testers kept track of every step. "We compared our step-count against the trackers', and all of the devices did well at counting steps." Next this metabolic analyzer was used to measure the calories each panelist burned. Some of the activity trackers proved better than others at counting calories. And some give feedback during your workout. Nicole Sarrubbo "Three of the trackers show how you're doing while you're exercising, and most of the panelists said they really like that feature." One that gives instant encouragement is the Fitbit One. The taller the flower, the more you've moved. It earned top ratings and costs 100 dollars. As for Joseph Jose, his tracker has helped him shed 40 pounds - and counting! ."