If, like me, you frequented arcades during the '90s, then you probably recognize this title from its glory days as an upright Neo Geo cabinet. What's interesting is that Metal Slug 2 is actually the third in the Metal Slug franchise to make its way to Android, after both Metal Slugs 1 and 3.
When you first launch the game, you can choose between Arcade Mode and Mission Mode. I prefer the latter, as it lets you pick up on the stage where you leave off, in case you need to take a break and shut down for a while. Meanwhile, Arcade Mode simply gives you 20 credits to get as far as you can. If you need to shut down or if the app unexpectedly quits, all is lost, and you'll have start at the very beginning.
Aside from the new title art and updated menu screens, Metal Slug 2 on Android has all of the same graphics as its arcade predecessor. Depending on how you look at it, this can be either a good or a bad thing. On one hand, the retro graphics help to evoke the nostalgia that makes playing old-school titles like this fun in the first place. But on the other hand, they are certainly underwhelming; they'll probably leave you wondering what a Metal Slug produced in 2013 might look like. In any case, the imperfect visuals of Metal Slug 2 are much less important than its actual gameplay.
While the game's controls have obviously been updated for today's touch-screen mobile interfaces, Metal Slug 2's gameplay on Android is just as addictive as it was in the arcade. There's a virtual control pad on the left side of the screen and three buttons -- Bomb, Shoot, and Jump -- on the right. For the most part, the scheme works perfectly, but if you find otherwise, you can always customize the key configuration however you like.