FireworX Stand is a very nice application for fireworks lovers. As its name suggests, you will see a stand where different types of fireworks are displayed. You can click on any of them to see a description of each firework rocket.
Under each of those there is a check mark. The check mark is there because those fireworks that are checked will be moved to the exhibition window when you go there. The exhibition window lets you test the fireworks. You can click on any of them to fire them. After you have clicked on them and they are selected, you can even click on a part of the screen to send the fireworks in that direction. All of the fireworks that I tried looked great, and the sound effects were quite good.
You can change a few options from the Settings window. There is a feature that gives the app itself full control of the fireworks: you can set how often the fireworks should be set off and just enjoy the show. Then, you also have mortar mode. When this mode is on, and you click on the screen, random shells will be fired. The other settings you can change are volume of the sound effects, background image, and color.
There is a free version that you can download from the Mac App Store. It has a limited number of fireworks, but it lets you test the app before you purchase it.