Activity Monitoring Fitness App

I'm looking to develop a comprehensive fitness app focused on activity monitoring with a strong emphasis on strength training. The app should not only track user activities but also provide a robust strength training module.

Key Features:
- Activity Monitoring: Real-time tracking of user activities.
- Strength Training Routines: A variety of strength training exercises.
- Additional Strength Training Features:
- Video Tutorials: High-quality instructional videos for each exercise.
- Progress Tracking: Detailed analytics on user performance and improvements.
- Customizable Workout Plans: Tailored workout plans based on user fitness levels and goals.

Ideal Skills and Experience:
- Experience in developing fitness or health-related apps.
- Strong understanding of activity monitoring technologies.
- Expertise in strength training and fitness program design.
- Proficient in video integration and analytics tools.
- Strong UI/UX design skills for a user-friendly experience.

Please provide examples of similar work and a detailed approach to meet these requirements.