I bought Mi Band 10 months ago. Xiaomi is my favorite brand beacuse they make really good products in affordable prices, I love collecting all gadgets from Xiaomi. So I wear it everyday and the results are very accurate, I verified it in many ways. It tracks our walking and running activities and keeps record of how much steps we go, and also sleep monitoring system is good it accurately keeps record of our deep sleep, light sleep etc.
Additional features are also fantastic like it notifies you through vibration for calls, messages, alarms etc. Its led has variety of colors also you can set it according to your choice. Overall this is one of the best activity tracker in affordable price.