Android Developer for npm package bug fixes and functionality improvement

I am currently facing some functionality errors with npm packages on my Android application. I'm in need of an experienced Android developer who can fix these issues for me.

Key requirements:
- The primary task is bug fixing, especially any issues that are affecting the overall functionality of the app.

Optional tasks:
- I may also need some feature enhancements, so experience with user authentication, UI/UX design, app performance optimization, and resolving app crashes would be beneficial.
- Knowledge of package dependencies and compatibility issues would also be an advantage.

Please note that this project is focused on resolving existing issues rather than developing entirely new features. A past record of tackling similar issues will be highly appreciated.

Thanks for your interest.