Time Management App Development

I'm looking for an experienced mobile app developer to create a life balance application focusing on time management. The primary feature will be a daily/weekly planner.

Key Features:
- Customizable themes
- Time-blocking options
- Integration with calendar apps

Ideal Skills and Experience:
- Proficiency in mobile app development
- Experience with UI/UX design for customization
- Knowledge of calendar integration

Please provide relevant portfolio work and estimated timelines.