When you add a new control to a form, it is not bound to a case field, making it a ātemporary fieldā. A temporary field can be used in rules, but the value in the field cannot be saved when you save the form in a case folder. In order to preserve the information in your control when the form is saved, the control must be bound to a case field. If necessary, controls with temporary fields can be re-bound to case fields either within the UI Designer (as described below), or through the App Designer, in the Field Mappings setting in Form Template Configuration (See App Designer Document, Form Template Configuration > Field Mapping)
Depending on your form type selection, the designer loads information from the case data model of the selected Case Type and Application.
To bind a control to a case field:
Select the control that possesses the same data type as the case field you intend to bind to. In this example a Text Box is added to the form.
When you click the Property for that text box then select Field, the lists of case fields with the same data type as the Text Box Control (shown as single line text eCASE) appears.

3. Assign the text box control to a field:

NOTES:
All the Core Fields of a case type can be bound to only āLabelā control except āAction Verbā core field. āAction Verbā can bind to either a āLabelā control or a āText Boxā control.
Lookup Dropdownā control can be bound to a case field of āLookup Dropdownā Field Type or āLookup Searchā Field Type. Similarly, āItem Pickerā control can bind to a case fields of āLookup Searchā, āLookup Multiple Valuesā or āLookup Dropdownā Field Types.
The core field āpriority_codeā cannot be bound to āItem Pickerā control and the core fields of āLookup Dropdownā Field Type in Contact Forms cannot bound to āItem Pickerā control.