1. Platform and License: Asana is a web-based task management platform that offers both free and paid subscriptions, while Redmine is an open-source project management software that can be self-hosted or used as a cloud-based service. Asana provides a more user-friendly and visually appealing interface, making it a popular choice for team collaboration, while Redmine offers more flexibility and customization options for larger organizations.

2. Features and Functionality: Asana focuses primarily on task management and collaboration, offering features such as task assignment, deadlines, comments, and file attachments. Redmine, on the other hand, offers a broader range of project management capabilities, including issue tracking, time tracking, Gantt charts, and document management. Redmine also supports plugins, allowing users to extend its functionality.

3. Integration and API: Asana provides integrations with commonly used tools like Slack, Google Drive, and Dropbox, allowing for seamless integration with existing workflows. It also offers a well-documented API that enables developers to build custom integrations and automate tasks. Redmine also supports integration with various tools, but its range of integrations is more limited compared to Asana. Redmine offers a RESTful API for integration purposes.

4. User Interface and User Experience: Asana has a modern and intuitive user interface, making it easy for users to navigate and learn the platform quickly. It offers a visually appealing design with drag-and-drop functionality for easy task management. Redmine, on the other hand, has a more basic and less visually appealing interface. While it may not be as user-friendly as Asana, Redmine provides a simple and straightforward user experience.

5. Customization and Configuration: Asana allows users to customize projects, tasks, and workflows according to their specific requirements. Users can create custom fields, templates, and tags to organize and categorize tasks effectively. Redmine offers extensive customization options, allowing users to define custom trackers, fields, and workflows to match their project management needs. It also supports user roles and permissions for enhanced security and access control.

6. Support and Community: Asana provides customer support through email and a comprehensive help center with detailed documentation and tutorials. It also offers community forums and a user community to share knowledge and get help from other users. Redmine, being an open-source platform, relies on community support through forums, mailing lists, and online resources. While community support can be helpful, it may not offer the same level of responsiveness as dedicated customer support.

In summary, Asana is a user-friendly and visually appealing web-based task management platform with extensive collaboration features, while Redmine is an open-source project management software offering more customization and a broader range of project management capabilities. Asana provides better integration options and has a more modern user interface, while Redmine offers greater flexibility and community support.