On the side menu scroll down and select the Farm settings icon.
Tap Field uses, here you can manage your Field uses.
Tap the three dots on the right of the input and then select "Edit"
You can view archived inputs on the manage inputs screen. You can also unarchive the input.
Go to Farm settings (cog on the top right) and select the Field usages tab.
Here you can select to Edit or Archive inputs as desired.
You can scroll down to view archived inputs on a list. If required you can also unarchive the input.