Xiaomi will again release a Mi band this year, and Mi Band 4 will replace Mi Band 3, which was released in May 2018. This has been revealed to Xiaomi during a conversation with investors. Of course, no details are given about the features of the new fitness tracker.
The Mi Band 4 will come in 2019, but you do not know exactly when. It is still not sure if you should show it in March or April, because the Mi Band 3 is still selling well. I would honestly reckon with May, 12 months is a good time for a successor.
The Mi Band brings always something new and that will not be different from the fourth generation. What that will be is still unclear. But it is becoming increasingly difficult to equip a fitness tracker with any special features. You can make this a little smarter.
The Mi Band may not be a gadget that Xiaomi makes a lot of money with, but it always goes down well and makes you look like a wearable maker. Fitbit has certainly snatched away one or two customers in recent years. But I would also say that Xiaomi goes one step further and possibly shows a real smartwatch.