If you mean something like the Body Bugg - they've come down in price, and the purchase includes a 6 or 12 month subscription. But I believe you'll need to renew the subscription to keep using the device. Not sure if some of the other brands don't require a subscription. As you research, be sure and check for reviews/user feedback. Cheap products sometimes don't work so well.
If you mean for tracking calories eaten, if you have a Smart phone - there is a Spark People app for free.
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