You can use your preferred barcode scanning application such as Barcode Scanner and Pic2Shop to capture input into a text or numeric field within a form. This is achieved using a custom menu item to launch the barcode scanning app and store the result in your field.
From the form designer, select "Optional Form Settings":
From the right-hand menu, select "Form menu and enhanced controls":
By default, the menu displayed during form conduction contains the items "Back" and "Quit". You can add custom items here such as "Scan barcode". Click the "+" icon to add an item to the menu. Next, choose "Any supported barcode format" as the action and give the item a label (e.g. "Scan barcode"). You'll see the preview of the menu update when you click "Add".
Lastly, you need list your "Scan barcode" menu item for the field(s) that you'd like it to apply to.
Return to the main the Form design screen. Add a new field or, if one already exists, edit it and navigate to step 3 "Custom Menu" as shown below. Select the custom menu items that should apply to the field (e.g. the "Scan barcode" menu item you added earlier). You can also decide whether or not the fieldworker should be allowed to manually enter data into the field or if it should only accept the result returned by the barcode scanner app.
Click "Finish" to save the field. An icon will display indicating that it has a custom menu applied. During form conduction, the fieldworker will be able to select "Options", "Scan barcode" to launch the handset's default barcode scanning application and return the captured result into the field.