Calcapp may be what you're looking for. You can validate text fields using regular expressions and there's an example of how to validate an e-mail address here:

Calcapp may be what you're looking for. You can validate text fields using regular expressions and there's an example of how to validate an e-mail address here: https://www.calcapp.net/learn/beyond-numbers.html#validating-text-fields https://www.calcapp.net/learn/beyond-numbers.html#validating.... Fields can be pre-populated with either values you know ahead-of-time or through Excel-like formulas. (I'm a co-founder of Calcapp.)