Tribu is a free social and communication application available on Android that aims to connect volunteers with local organizations. With Tribu, users can easily find and apply to various volunteering opportunities in their area. The app also allows users to report their volunteer activity, chat with other volunteers, and share their experiences with friends.

One of the unique features of Tribu is its ability to access the file system of the user's phone. This allows users to upload important documents, such as legal permits and CVs, that may be required by certain organizations. Without these documents, users may not be able to volunteer for certain opportunities. While this feature may raise some privacy concerns, it is a necessary component for users to take full advantage of the app's capabilities.

Overall, Tribu is a great tool for those looking to give back to their community and connect with other volunteers. Its user-friendly interface and unique features make it a standout in the social and communication category.