Certain types of games abound in Apple's App Store, and one genre that seems to be everywhere is tower defense. But even amongst the glut of similar games, Epic War TD stands out from the pack with excellent sound, graphics and a slew of customization options.

For the uninitiated, tower defense is a subgenre of strategy games, where players are presented with a winding path that they must defend from attackers. This is accomplished by placing towers in between rounds that can fire at attackers as they march toward the endpoint. Typically, players are given a set number of lives that decrease with each attacker that makes it through the user-created gauntlet.

While it's a simple concept, Epic War TD does wonders with it in a number of key areas. The first thing that pops out when playing the game are it's graphics, which are among some of the best on the iPhone. Adding to the visuals is the fact that many of the unit designs appear to be based on, or at least inspired by, the blockbuster real-time strategy game series StarCraft. Seeing crawling insect monsters and marching space marines wind their way across the screen adds a lot to the gaming experience, and is much preferable to the generic denizens that populate many other tower defense games.

The best graphics in the world can't make up for uninspired gameplay, however, and fortunately Epic War TD delivers there as well. Just as in other, similar games, users spend their in-game money to place towers at key, strategic areas. Epic War TD features five distinct tower types, each with their own strengths and weaknesses, so there are a lot of choices to be made when it comes time to spend your dollars. Since different attackers each respond to the available towers in unique ways, gamers must not only put towers in the right places, but also make sure they purchase the correct ones.

Many tower defense games offer gamers the ability to upgrade their units, but too often the upgrades are of nominal value, with your money better spent on simply building more towers. Not only does each individual upgrade in Epic War TD make a noticeable difference in gameplay, but players are given the freedom to choose from any of three attributes to level up.

The available upgrades include damage, range and attack rate and give gamers a large degree of freedom in customizing their defenses. With the numerous tower types and deep upgrade system of Epic War TD, players can set up an array of quick, weak towers backed by a slower, stronger attack unit, or any other combination you can imagine. Additionally, depth is further added with the inclusion of special "super upgrades" that give each tower a distinct bonus, such as splash damage or the chance to score a critical hit.

A possible complaint with Epic War TD could be that the game only features four levels. While each one includes multiple rounds, it's still a disappointing amount of gameplay for the app's $2.99 price tag. Fortunately, however, Epic War TD is a considerable challenge, even on its easiest setting, and will likely keep most gamers busy for longer than they would expect. Additionally, the makers of Epic War TD have promised additional updates that will add new levels and enemies to the game.

In earlier versions of Epic War TD, the game was plagued by freezes and crashes, unacceptable for any professionally made product, especially one with a relatively high (for the App Store) price tag. However, the game's first and most recent update seems to have solved all of these problems, demonstrating a commitment by the developer to continue supporting Epic War TD.

For the most part, the gameplay in Epic War TD is unimpeachable, but one small complaint arises with the transition from one level to the next. Instead of maintaining any additional dollars when clearing levels, users are knocked back down to a starting dollar amount. While it is still possible to beat levels by spending your money wisely, it stands to reason that if your lost lives are carried over from level to level, your money should be as well.

That's a small complaint, however, which does little to detract from the greatness of Epic War TD. With it's clear, crisp graphics and wealth of in-game upgrade options, it is easily one of the best tower defense games available in the App Store, and a wise purchase for any fan of the genre, or even someone looking to experience it for the first time.

Final Score: A