You can extend the functionality provided in Spread to end users through other controls on the form. The Formula Provider extends the formula and function capability to other controls on the form. The Formula Text Box can be used to make formula bars or other edit controls in your application. The Name Box can be used to add custom names in the application. These controls extend spreadsheet capability to other parts of your application.
For more information on formulas, refer to Managing Formulas in Cells and the Formula Reference.