The instructions are a bit hard to read but was able to use readers to help. Easy to set up and link with micro sim or bluetooth. Lots of useful functions but the more you use them the quicker the battery drains. I did not check the accuracy of measuement. Battery is ok but could be improved as could the sync app. The watch band could have more give which would make it more comfortable. Overall a great entry level smartwatch. Note that this was used with Android devices.