To combine two layers, you merge an active layer with the one directly below it.

1. Go to the Layers menu and tap the layer you want to merge to make it active.
2. Tap the active layer a second time to open its menu.
3. Tap the merge icon, which looks like two downward-pointing chevrons.

Important: The active layer will merge into the one below it. The properties of the lower layer (such as its name and opacity) will be applied to the newly merged layer.