Worked on the stone-payments/demo-sdk-android repository to deliver Submerchant Information Handling and TaxIdentificationType support, focusing on enhancing payment processing and compliance for merchant onboarding. Upgraded the Android SDK to version 5.6.0.3 and aligned Gradle dependencies to v4.15.0, ensuring compatibility with modern Android development practices. Updated the sample application to reflect new submerchant tax identification features, preparing the codebase for expanded regulatory requirements and onboarding flexibility. Utilized Java and Kotlin to implement these changes, emphasizing SDK development and payment processing improvements. Prioritized compliance and processing capabilities over bug fixes, contributing to a more robust and adaptable payment platform.