Now you can study the Rules of the Road direct from United States Coast Guard test bank. The 1057 questions include all the pictures as provided with the official test. In addition, tips for the test are provided on startup (e.g. Key phrases to memorize.) This app does not need use the Internet, so it works great on airplane mode when you are in the middle of the ocean.
Since this is the Pro Version, you get many additional features: a low light setting, a picture gallery, a glossary of terms, a breakdown of the hierarchy of vessels (Rule 18), cheatsheets for sound signals (Rules 24 & 25), direct navigation to specific questions, and quiz settings.
This app is continuously improving thanks to user feedback. However, as I am a mariner myself, there will be significant periods with no updates while I'm underway, but I'll still get your feedback.