I wanted to make this app with flutter because I was interested in flutter developer roles. I figured out this payment interface is a fundamental and common fragment of almost every app, since almost every app requires some sort of payment/transaction interface to be present, be it a video streaming service like Netflix or Disney+ during signing up for subscription or a social networking platform like facebook or Instagram where an user needs to add their card details for promoting their content to reach more users. I wanted to build something that would cover demonstration of a wide range of skills required for an app developer, like - knowledge of architectural components & design patterns, state management/nested state management with provider, fetching data from servers to demonstrate proficiency with restful API to connect applications to back-end services, building a real time interface, using the Camera API, writing data to local files, custom navigation stack, complex animations, seamlessly incorporating third party packages, pixel-perfect implementation of UI designs (differs only because some improvisations I made), debugging, analysis skills & performance tuning and deployment to playstore.