SAN FRANCISCO – The more phones that hit the market using Google’s Android operating software, the harder it is for each offering to stand out from the black-and-silver crowd.

Samsung is the latest company trying to turn heads, hoping consumers will snatch up its Galaxy S smart phones, which are both attractive on the surface and well-appointed under the hood.

AT&T already sells the Samsung Captivate, and T-Mobile offers the Vibrant. Two more are coming: Sprint will start selling the Epic 4G at the end of August, and Verizon plans to roll out the Fascinate this fall.

I tested the Captivate, Vibrant and Epic 4G, which all have plenty of great features in common: bright, crisp screens; 5-megapixel cameras that can also take high-definition videos; speedy 1 Ghz Hummingbird processors; and Google Inc.’s easy-to-use Android operating software.

With all this and more, one of these may be the ’droid you’re looking for.

Probably the most obvious feature on each Galaxy S phone is a sharp AMOLED touch screen that runs 4 inches diagonally and dominates the face. AMOLED screens tend to have higher color saturation than standard LCD screens, and they can be thinner. In plain English, it meant that the videos I watched looked great – sometimes even better than on Apple Inc.’s new iPhone 4.

I was also jazzed to see that each of the phones includes Swype, a new third-party application that lets you type on virtual keyboards by simply swiping your finger around from one letter to the next. The phones are packed with version 2.1 of Google’s Android operating software, which means you get features such as voice-recognition capabilities for dictating e-mails and instant messages and the Google Maps Navigation application for obtaining turn-by-turn directions. They’re not starting out with the latest version of Android, though, which has even more voice command options.

The phones have plenty of memory, too: The Epic 4G includes a 16 gigabyte microSD memory card, while the Captivate and Vibrant have the same amount of internal storage.

Beyond all the similarities, there are plenty of things that make each Galaxy S phone unique:

Samsung Captivate

(AT&T, $200 with two-year contract).

The Captivate is a sleek, thin slab of a phone — heavier than the Vibrant but just as skinny. It fits well in a back pocket and is easy to hold and type on using Swype.

The Captivate is rated for even less talk time than the Vibrant (just under 6 hours, at best) but it did seem to conserve power better than its sibling.

I was impressed by Captivate’s responsiveness, as it rarely froze up.

Samsung Epic

(Sprint, $250 with two-year contract and after a rebate).

Rolling out Tuesday, the Epic 4G will work on the standard 3G cellular network and the newer-generation 4G network from Sprint. You’ll need to live in Seattle, Chicago or one of the other 46 markets where Sprint now offers 4G to try both, though, and it will suck up more battery life. Otherwise, like myself, you’ll be using it on 3G.

The Epic is the only one of the bunch with a front-facing camera so you can video chat over a built-in program called Qik or stream video live to Qik’s website. Size-wise, the Epic is a bit of a beast. It weighs nearly 5.5 ounces — more than the other two Galaxy S phones I tried. That’s largely because it also has a standard QWERTY keyboard that slides out; it may be the largest I’ve come across thus far. With these initial Galaxy S phones, Samsung managed to cram an impressive amount of features into good-looking packages.

Samsung Vibrant

(T-Mobile, $200 with a two-year contract and after a rebate).

Though the Vibrant’s black body with silver trim looks like an older iPhone, it distinguishes itself by being a generally solid Android phone that’s good at multitasking.

The phone is the lightest of the bunch, tipping the scales at 4.2 ounces. The biggest issue I had with the Vibrant was its battery life. The phone is rated for up to 6.5 hours of talk time. That should be plenty for voice calls, but if, like me, you’re more interested in checking Facebook, taking photos and surfing the Web, this phone will run out of juice by late afternoon.