Can I have a choice between two fields for a required field?

For example, I would like a contact number provided but I am not concerned whether this is a mobile, business or home number.  Is there a way to force that I get at least one contact number rather than making all fields required?

Of course. You can add the Condition for making this from our Settings panel. I have made a sample form that fits your situation. You can find sample form here.

There are 3 different phone numbers in the first picture.

In the second picture, I have created 3 conditions to make possible what you wanted. You can easily select what to do according to if conditions.

If you have any further questions, please share with us. We will glad to solve your problem.