Everytime you're on the bus and you see a company sign , think to yourself.."What kind of app could help this company?". Instead of waiting for clients to come to you through advertising, develop goodlooking MVP's , go to them and pitch your ideas. Trust me you will be surprised...That pizza spot at the corner that everyone in the neighbourhood loves?...don't you think a ordering app would grow their business? Same as the dry cleaner that has pickup and delivery service etc?

This shouldnt be too difficult when it comes to developing an MVP as I see you posted your question as a React Native application. I personally prefer the Ionic Framework for its easier learning curve and speed in development especially for developing bare bones demo apps as it has quite useful templates by default(not sure about React though). But either way, stick to tools you love and understand.

There is so potential out there, most clients don't know they need an app until they see it in their hands. Go out there and make some moolah.

If you need any more strategies I use just comment below,but I hope you get the vibe.