Integrating Advanced API Solutions into Full-Stack Web and Mobile Applications to Optimise User Experience

Abstract : The impact of integrating Stripe, Firebase and OpenAI in advanced API solutions, which is investigated in this research, is to optimize user experience (UX) in web and mobile applications. Based on a case study analysis of actual applications that have already adopted these APIs, the study uses empirical data collection, performance metrics analysis, and user feedback analysis to test whether these APIs are effective or not. Experiments are performed to analyze API integration, and the performance of the application before and after API integration is compared. The success rate of transactions, data synchronization speed, and AI-powered engagement metrics were used as KPIs to measure the impact on UX. To complete the evaluation, data was gathered from application logs, user interaction reports and developer insights. The study defines UX optimization as loading speed, ease of navigation, transaction speed, real-time responsiveness, and engagement levels. According to our results, Stripe reduces the checkout abandonment rate by 40% and improves the transaction success rate by 30%, thereby boosting user trust in transactions as well as transaction efficiency in terms of finance. This cuts down around 70% for data synchronization latency, which gives for a smoother app experience and better retention rates. The AI models from Open AI enhance the session times by 25-40% and grow engagement by virtue of engaging the user better with a more personalized experience for the user. Science verifies the particular advantages of integrating API, including latency reduction, improved interactivity, and speed of application processes. All of these are highlighted as integration challenges in the research, as well as the best practices for future API implementations. This study is a good start to suggest ways of optimizing UX with the adoption of APIs.