Expressions can be used to bind variable values of data (such as date, time, battery level, steps, and heart rate) and attributes (such as x-coordinate, y-coordinate, font size, and color) on the watch face layer, and work with mathematical formulas, function operations, and conditional statements to define the change modes of watch face content. You can use expressions to design highly customized, dynamic, data-responsive, and creative watch face content.
Watch faces created by using expressions are supported only on wearables running HarmonyOS 7.0 or later. Wearables running versions earlier than HarmonyOS 7.0 are not compatible with this capability.