Select a field from the list to open the field card. Then click the three dots in the top-right corner. Tap the Remove button. All done!

In the Fields tab, select one or more fields from the list using the checkboxes to their right and click Delete at the bottom of the screen.

Or, select a field by clicking it in the field list, then click the three dots in the right upper corner of the Status tab, and then, Delete Field.

You can also delete a field by clicking the three dots, then selecting Edit Field → Remove Field From ....