I have used a Mi Band as a smartwatch / fitness tracking device for the last couple years. Compared to, say, a Wear OS device, it offers a vastly better deal: It’s cheap, at around 30-40 CHF. The battery lasts several weeks. It shows the time and tracks steps and movement. The Wear OS device costs 5-10 times as much and needs daily charging. To be fair, in addition to showing the time and tracking fitness data, it does many other things that I don’t need.