Strap keeps good data for sleep. I've found that tracking activity using it for lengthy runs - over 2 hours - is useless as the app freezes and I basically have to uninstall it and reinstall. Honestly for the limited use it has for my fitness tracking without the Ap freezing it's not worth the over 300 that I paid for the fitness package and will probably be returning it. You would think that using the shoe pod during a run would track stride and cadence - it does neither that I can see. Just disappointed overall - there are fitness watches that do everything this strap, hr armband, and POD do for the same price or lower