Comprehensive LSRW Mobile App Development

I need an Android app to enhance Listening, Speaking, Reading, and Writing (LSRW) skills. The app should have:

- Interactive Exercises: Engaging tasks for all skill levels.
- Progress Tracking: Personalized dashboards.
- Audio/Video Lessons: High-quality, immersive content.
- Differentiated & Segmented Learning Pathways: Tailored learning experiences.

Ideal candidates should have experience in:

- Mobile app development, particularly on Android.
- Designing educational apps with a focus on language learning.
- Creating interactive content and progress tracking systems.
- Integrating audio and video content seamlessly.

Please provide samples of similar work done.