Yes! It is! On your "Activities" page click on the folder you would like to make a subfolder in. Once in the folder click on "New" in the upper left hand corner then select "New Activity" to create a single activity in the folder or "New Folder" to create your subfolder. 

• When clicking "New Activity" the "Create Activity" screen will appear. Create your activity as you normally would! It will appear in the folder. 

• When clicking "New Folder" a "Create Folder" pop up will appear. Type the name of your folder and choose the color then be sure to click on "Confirm." Your subfolder will then appear!

• When clicking "Import Multiple Activities" a pop up will appear. Paste the sharing links in the pop up then click "Import from sharing text."

Have fun organizing!