Yes.

Deby.AI offers a free of charge starter license. With this license, you can experiment with all the features of Deby.AI. You may permanently utilize your apps and views for commercial applications. You may create application prototypes and demos as well.

Please see here.

Besides of the built-in field validation, Deby.AI supports the following input validation methods:

• Text fields can be validated by defining an input pattern. (e.g., zip codes)
• Text fields can also be validated by specifying a JavaScript regular expression. This expression is evaluated whenever the end-user types a character.
• A JavaScript validation snippet can be defined on all field types.  This snippet is executed whenever the end-user types a character providing a powerful and detailed error detection.
• Cross-field validation is done by specifying a form-level JavaScript snippet. This snippet is executed when the end-user submits the form.

You may define money fields in any currency. You may control the field input currency and the currency displayed to end-users. For details, please see here.

You may fully control views and apps user permissions and authentication. Please see here.

Yes. Please see here.