Productivity Mobile App Design

I need an experienced app designer to create a productivity mobile app. The key functionality of this project involves creating an interface that boosts productivity for users.

Skills and Experience Required:

- Proven experience in mobile app design for both iOS and Android platforms for all form factors
- Knowledgeable in rapid prototyping
- Strong understanding of UI/UX principles
- Ability to work with feedback and execute multiple revisions as necessary
- A portfolio showcasing previous work in similar projects would be highly beneficial.