FitBit - My fitbit is a fitness tracker, heart rate monitor, and (most of the time) my activity motivator. I've owned a Fitbit since the product first arrived on the market back in 2009. I can set goals for weight, steps, workouts and more then track my progress. Eventually I can share that data with the Nutrisystem NuMi app but currently the app is not functioning. It will be very helpful when it all synchs together. I've used various versions of the Fitbit and I'm currently using the Charge HR model. I'm very progress oriented so I really like the graphs and details they provide. Everything synchs up with my iPhone which is very convenient. The Fitbit can be purchased directly from the company or at many online retailers. If you're on a budget you can watch Groupon for specials on refurbished units which offer a good savings.
Aria Scale - My Aria scale tracks my weight and body fat percentage. I'm not 100% those percentages are accurate but I can see the trend which really is all important to me. Once I weigh it is connected to my Wifi and reports back to my FitBit dashboard. Eventually it too is supposed to synch with the NuMi data but that remains to be seen. I purchased mine directly from FitBit buy you can buy them at Walmart or Amazon.