Hierarchical labels are available only on full version
Tap on icon on top left to open slide menu
Select Labels on slide menu to see all labels
Tap on the icon on the right of a label that you want to add in a parent label
Here you can add items to Child1. To create a hierarchical label tap on Labels to assign a label to Child1
Tap on Parent to add Child1 to Parent label. You created a hierarchical label! Parent label contains Child1 label, now you can add Parent label to Android home in the usual way
You can assign more items to a label easily. Tap on the icon on the right of Parent label
Select the items you want to add to Parent label. Adding labels to a label you can create a more useful hierarchy of labels!