Do you need to report an incident of police violence to somebody that isn't the police? Five-O might be the app for you. Built by three teenaged siblings from Georgia, US, the app is designed to track and prevent police brutality – and with ongoing protests against the tragic Ferguson shooting of Michael Brown, it can't come at a more necessary time.

On Five-O, users can record if they were physically assaulted by a police officer; they can also enter their race and gender, as well as rate their overall interaction with police. The app uses the demographic information and data to build up a mean rating of policing in each American city. Communities can use the rating to campaign for change and improvement.

Handily, the app also comes with a "Know Your Rights" feature – meaning that if you believe you're being treated unfairly by an officer, the answer's in your pocket.