Referee Tools, developed by LuckyWorks, is a free Android app designed for soccer referees that provides them with a set of useful tools. With Referee Tools, referees can easily issue a caution with a yellow card or send off a player with a red card, whether they are on the field or at home. The app also features an integrated whistle that can be blown to signal the start or end of the game, as well as a coin flipper for making important decisions.

One of the best things about Referee Tools is that it is completely free and doesn't contain any ads. The app is easy to navigate and use, with simple and intuitive controls that make it easy to issue cards or use the whistle. While the app is primarily designed for soccer referees, it can also be used by coaches or players who want to simulate a referee's decision-making process. Overall, Referee Tools is a handy tool for anyone involved in soccer, and LuckyWorks is open to feedback and suggestions for future updates.