Ah, the classics. Shakespeare. Beethoven. Space Invaders.

The days of pumping quarter after quarter into a bulky console to feel the thrill of fending off primitively rendered space-monsters are gone, but the fascination remains. Back then, the consumer spent two bits for eight-bit graphics and considered it a bargain. The action had to be simple and extremely addictive, because it wasn't going to be realistic or visually lush. That bred extremely addictive and playable games.

We searched for the best versions of arcade classics for the iPhone, and here is what we found:

Space Invaders, Taito ($2.99): With classic arcade games, you have to decide whether you are looking for the perfect iPhone copy of the original, or whether you want what the game could have been, with slightly more memory or processing power. Taito favored nostalgia, producing a miniature Space Invader console, down to the artwork on the machine itself. Bonus: includes original "bad guy" pen-and-ink doodles, answering the age-old question, "what were they thinking?" If you're not familiar with the game, wave after wave of evil two-dimensional aliens descend upon earth firing missiles, and eventually always kill you. You know, the Gen-X thing.

PAC MAN, Namco ($4.99): Before PAC MAN was a misbehaving football player, he was a round guy that ate energy dots in a maze, pursued by angry ghosts. Namco's faithful reproduction recreates 100 levels of the lost youth of America's middle-aged population. Want a one-level sample? Try PAC MAN Lite. Also available: Ms. PAC MAN. It's different because the hungry pie-chart has a bow and lipstick.

Galaga Remix, Namco ($4.99): Namco's also done for Galaga what it did for PAC MAN, but struck out in their own direction as well, updating and upgrading an alternate version of the game in the same app. The classic game plays just like the original, except that the controls are tougher to handle, because they're about 1/10th actual size. Still the best Galaga re-make out there.

Guardian Missile Commander, Trenton Henry (free): For our money, the free Guardian raises the ante on Atari's $4.99 Missile Command. Guardian only slightly updates the 2-D graphics of the original, whereas Atari does a full reload (but also offers a "classic mode.") Guardian re-interprets the original's logic, building its features level by level. Where it shines is the plot device that puts each level's new features into context through Associated Press and Intelligence reports. I found myself believing--and remembering my classic Missile Command games a whole new way. Oh, the humanity....

iJoust Classic Arcade, Ecoshop Holding LLC ($0.99): Joust involves a number of fanciful improbabilities. The Joust world consists of overhanging rock ledges, and is populated almost exclusively by knights mounted on flying ostriches. Collect golden eggs for some reason, and use the "Magic" button to fry the enemy en masse. If you understood the original arcade classic, you'll get iJoust Classic Arcade. The gameplay and graphics are just about identical. Sentimental favorite; An old girlfriend once opined, when the local machine's Magic button broke, "the magic has gone out of our relationship."

These simple games will evidently be with us for a long time after their original relevance has expired. Whether you're new to the genre or an adult survivor of early video-game addiction, these apps will surprise you with their elegant simplicity.

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