During December 2024, this developer enhanced the bullbitcoin-mobile repository by implementing PayJoin URI parsing within the Sender flow. Using Flutter and Dart, they engineered a solution that extracts the 'pj' parameter from BIP21 URIs, converts it into a usable PayJoin endpoint, and stores it in SendState for downstream processing. This work enables the app to initiate PayJoin requests, directly supporting privacy-focused payment strategies and improving compatibility with PayJoin-enabled wallets. The feature demonstrates a focused approach to mobile development, addressing a specific privacy need with a targeted, well-integrated solution, though the scope was limited to a single feature during the period.