Pro Buoyage is an easy to use platform that initially teaches you Region A & B using digital flip cards.
Once you have mastered Region A & B , there is a range of different questions and scenarios, that help you to fully understand what they are and what action you should take upon seeing them at sea.
There are also UK coastguard (MCA) replica tests that help you get up to speed, of what would be expected during an orals exam. This is useful for cadets or anyone looking to upgrade their licence.