Call of Duty: World at War is hitting most major platforms, and the series revisits World War II for a second tour of duty on DS. Subtle improvements and a return to a tried-and-true FPS (first-person shooter) formula make this a fun, little shooter on the go.

Though Call of Duty 4 (CoD4) was a major overhaul for the series – bringing the action into the present – Activision has decided to venture back in time for one last look at what are perhaps America’s most memorable moments in military history. You’ll play from three different perspectives: American, British and Russian, and the different locales and weaponry definitely serve to inject at least a little something new into the WWII FPS experience. World at War follows very familiar patterns, however, so if you’ve been down one of these war-torn roads before, you should know the gameplay drill.

World at War DS offers a healthy selection of gameplay options. For single-player, you get Campaign, Missions (which allows you to go back and play specific portions of the campaign already completed), and Challenges. The campaign is broken up into bit-sized gameplay segments, and the checkpoint system makes play on the go an easy proposition.

Campaign first runs you through the American missions, as they take the fight to the Japanese. The game sticks with a similar training regimen as that of CoD4, and you’ll be brought up to speed on all the basics right from the start. Once in the field, the terrain offers a new and interesting topography that’s a nice change from the bombed-out cities of Europe. Of course, you will eventually make your way westward, playing as both the British and the Russians, as they push back the German troops.

World at War is an FPS, and its controls are much the same as the last CoD on DS. However, the double-tap technique used to zoom in during long-ranged shooting in the last game has been swapped out in preference of an actual zoom-in icon located on the top-left of the touch screen. The zoom-in feature in CoD4 DS was a significant issue in the last game, as you’d often zoom in or out at inopportune times. There was no option to adjust the screen sensitivity, and constant issues with your gun sight were a source of contention throughout much of the game.

The controls work well in pretty much all areas now, including various mini-games you’ll play throughout the campaign. One mini-game tasks you with disarming a land mine, and the feel, intuitiveness, and order in which you’re instructed to perform each action makes sense and is fun to play through. There are a handful of other clever and well-implemented mini-games, including one where you’ll need to patch up an injured soldier, as well as one where you’re tapping out Morse code. Of course, there are also plenty of on-rails segments, and the controls for tanks and such all function well.

As you progress through missions, you’ll constantly receive new objectives. They flash onscreen pretty fast, and if you’re in the heat of battle when you receive your latest objective, it’s easy to overlook what’s been instructed. That said, you can press the Select button to enter a map menu that briefly explains the objective and gives you its general location. Additionally, the hub located on the touch screen during gameplay houses a radar that shows you the direction you need to be heading, reveals enemy and ally locations, as well as alerts you to nearby ammo.

There are, however, a couple of issues that impede progress a bit. One complaint has to do with the lack of clear explanation about how to properly use some of the heavy artillery you’ll man during missions. Occasionally, you’ll be thrown onto a weapon you have no idea how to use, and an inevitable trial-and-error process will require multiple stabs at an objective.