The Customization In-App purchase unlocks the most powerful features in CALC 1 to help you reduce mistakes and save time.
Creating a new key to store a formula you use is similar to creating a Contact to store a phone number. Most of the time you copy a formula you already entered from the History List and paste it in the Key Editor. Then give it a label and you never have to enter that formula again!
Customization with CALC 1 does not involve programming. You enter spreadsheet compatible formulas and functions into the Key Editor or Formula Calculator Editor.