If you already have a prototype (an App or a physical product) then it is important to have some quantifiable feedback. For example:

(a) You have active users on your platform who have given you feedback regarding the effectiveness of your solution (lowered costs or other benefits – expressed in percentages or absolute values).

(b) If you have a physical product then you have proven its functionality and possibly have some commitments from retailers, companies (if B2B) or pre-sales from end-users (if B2C).

This shows that your project is functional and that there is a market demand/benefit.