Creating custom formula is a powerful feature and it is a beginning to providing excel-like functions in Zoho Creator. Even the simplest of applications like a student marks database( given below as an example) or an expense tracker (to calculate the total expenses) requires custom fields that are calculated based on the values of other fields. They have to be created while defining the form and could be numeric, text, date or boolean.

* You can create calculated fields by selecting the field type as formula.

* All the types of form fields except multiple select fields can be used in formulas.
* The operators / functions that can be used in formulas can be found in the Deluge docs.
* The formulas will get recalculated when
  a. the formula is modified
  b. the values of the fields participating in the formula gets modified (when a record is updated).

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#2 How do I keep few tabs private and others public?

Follow “Manage Users” link and select “Sharing”. In the “User/Group list”, select “Public Visitors”. Expand your application and remove the selection for the tabs you want to make private. Tabs selected under “Public Visitors” will be public and tabs that are not selected will be private.

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