SwipeSimple Web
When adding a new item or editing an existing item, select the checkbox next to "Keep track of inventory". Using the "On Hand Count" field, set the current quantity of the item you would like to track.
SwipeSimple Mobile
When adding a new item or editing an existing item, toggle the switch next to "Track Inventory" and then update the quantity field above the toggle that highlights. Once you've done that, click "Create" or "Update Item" to save.