prototype Campaign

I want to raise money to pay for a prototype. There's a messaging app that I want to create and I have applied to an application builder company and they gave an estimate fee for the whole project but before that a fee for a prototype is needed. For the app to come to life a prototype is needed, so the funds are for the prototype This app has a potential of a big turnover and can also help and bring smiles to people around the world for example to those that don't anyone to talk or turn to .  The money is strictly for a prototype.