It looks like Call of Duty, and it sounds like Call of Duty. That's quite a victory for the team at n-Space, as developing a game from a series known for its scale and multiplayer on a handheld is no easy task. It's clear they've sunk a lot of effort into making an authentic Call of Duty experience.
They succeed in quite a few places. The player will instantly recognise the game's diverse weapon selection - laser sights and all. In addition, Mobilized is always talking to you, with VO briefings before each mission and pretty constant chatter throughout, which is a nice treat for DS owners, who don't usually get a whole lot of voice acting. The sound effects complement the action well, with each weapon producing proper noise and plenty of suitable "booms". The background music is good stuff too, with an epic score to set the mood.
Despite getting these things down properly though, the game has several flaws which can't be ignored. One is the very slow framerate, which is unfortunate as this flaw saps a lot of enjoyment from the game. It's stable, but it's always moving much, much slower than I would have liked. It's understandable considering all the team at n-Space is pushing here: six to seven soldiers on screen at once, large outdoor environments, decent character models and animations, and a solid amount of nice effects. But I'd really rather they had scaled the game back a few notches to get Mobilized moving as it should. Its console brother has a fast and smooth feel to it that this game lacks.
Eventually you do adjust to the frame rate; it may be frustrating, but the game is still playable. Get that out of the way and there is a pretty good game here to be played. The campaign is fairly lengthy - longer than ones you'll get on the home consoles, even - and offers a generally fun experience. The best thing the developers have done is constantly mix things up. In one mission you will be riding in a helicopter and in another shooting shore-bound enemies as you sit in a boat headed down stream. They've also sprinkled some touch screen mini games throughout, like hacking computers and breaking codes. For the most part these do a good job of changing up the pace, but some of these elements are hit or miss.
This leads me to my next issue with the game, the consistency of the campaign. Some missions are frankly a pain to go through, with a few of the unique elements - one particular tank scenario springs to mind - being more irritating than fun. To compound this frustration, the game is rather ruthless even on the easier settings. You'll die several times per mission - thank goodness checkpoints are frequent. However, there are also many levels - particularly towards the end of the campaign - which are excellent, including a great helicopter mission and an even better AC130 scenario. The ground fights are much better in these levels too, with the developers changing up the enemy encounters and the objectives. It's a real shame that this level of quality isn't consistent throughout the entire game.
Of course one of the biggest questions for any DS game is how the touch screen controls work, and the answer is "pretty well". Changing weapons is quick and intuitive, and bringing up your iron sights takes only a quick tap. It's a solid system that works, but you'll definitely want to bump the sensitivity up as much as the game allows. The controls in some of the games more exotic scenarios can frustrate at times (the aforementioned tank mission again comes to mind).
The multiplayer is something they can be fully proud of though, being the first FPS on the system with six player online matches. It can be a challenge at times to actually match up with six players, but it's good fun when you do, and still enjoyable if you can't quite get a full match. I prefer the hectic and fast action of Metroid Prime: Hunters, but n-Space deserves credit for bumping the capacity up by two more players than Nintendo's effort.
Like many war games, it's a bit drab, but the game pushes the DS well with large environments, nice effects, and a lot of action on screen. The framerate, though for the most part stable, really needed to be brought up.