Free games to play on your iPhone

Not all games have been optimized for the iPhone equally. In fact, I found quite a few clunkers that seemed to exist only to take your cash, advertise dubious services, or bombard you with cut-rate graphics. Shudder. These five games, added just this month, test your strategy and timing while offering above-average graphics.

Don't forget to review the games on CNET Download.com, or serve up your own favorites in the comments below.

501 Darts is a two-player strategy game that pits you against your cutthroat iPhone. The goal is to roll down your points from 400 to zero by lobbing darts where it counts--in the highest point zones possible. Tap the red button once to set your horizon and once again to choose the vertical axis. Then watch the arrows fly. The game is fun, but lacks settings to change the game style, pause or save a game, or even reduce the points if you want a shorter game.

501 Darts is free, supported by a banner ad that doesn't obstruct the graphics, though it certainly won't beautify them either.

The same publisher, Ion Games, brings you Golf Driving Range, which uses similar horizontal and vertical bars tirelessly vacillating between extremes to set the direction and strength with which you hit. It behooves players to also pay attention to wind direction and the course schematic while planning their shots. The iPhone's timing eluded me for the first two games, but as I started getting the hang of how to plan my taps, frustration melted into personal challenge.

You can always tell Sudoku sovereigns by their intense, withdrawn stare. Addicts of the Japanese puzzle game can solve a daily conundrum for free, and ad-free, with Radworkz Daily Puzzles. Insert a digit into the appropriate square by tapping the square once and selecting from the number wheel.

Sometimes the simplest game is the most satisfying. Connect4 touch is one of those. The iPhone-generation's high-tech take on the classic two-player game again matches wits with your Apple's AI to see which player can line up four colored circles first. This one is ad-supported, but once you click the "play" bar below the ad, the game is nuisance-free.

A new day, a new puzzle--that's iFreecell's philosophy. Each day, tiles of three designs are shuffled into a 64-square grid. Your job is to remove the tiles by clicking the designs--but those social tiles only disappear when they have a companion. Use your noggin to click away the adjacent or stacked tiles without leaving any singletons behind.