Having solid experience working as a full-stack developer for the past three years, I'm confident my skillset aligns seamlessly with your need for a React Native developer. Not only am I adept in React Native, but also bring extensive knowledge of iOS submission and approval process to the table. This familiarity is an asset when it comes to implementing In-App Purchases (IAP) and ensuring smooth functionality.
Regarding your key responsibilities, I've successfully handled implementation of various subscription models, including "single tier subscription", which makes me well-versed in their subtleties and intricacies. Therefore, you can trust me not only to update the app but enhance its user experience as well.
Revamping and enhancing apps is not just about delivering high-quality solutions; it requires a deep understanding of the app's purpose and the user's expectations. I believe my multidisciplinary expertise coupled with my dedication will make me your ideal candidate for this project. Let's work together to take your app to new heights!