You can develop an idea, interview potential users and make a simple prototype with free tools and your own time. A live product can introduce hosting, store account, integration, maintenance and support costs. Check free-tier limits and plan how the service will be funded before relying on it for customers.
Testing an app idea on a limited budget
Early research and sketches can expose unclear requirements before you commit to a build. Free tools can support experiments, but review their usage limits and the costs of operating a live service. Your own time, customer support and maintenance remain part of the investment.
Planning your mobile app project
Interview potential users, map the main task and test a simple prototype. Record the evidence you need before funding a working product and set a realistic ceiling for ongoing costs.