What are the best ways to develop a cost-efficient mobile app?

Hello there. I’d like to develop a mobile app with cutting-edge functionality. A rider app, a passenger app, and an admin portal are all included. It is necessary to register and edit your profile. Can someone provide me with a cost estimate for app development? or else any other way to get a cost-efficient mobile app for my taxi business?. Is anyone aware of the development field please help me with it?