Designed to take on Apple's iPhone, NTT DoCoMo Inc. released its new Galaxy S handset Thursday into Japan's increasingly competitive smart phone market.

Teaming with Samsung Electronics Co., the world's top electronics firm, DoCoMo aims to increase its share of the domestic smart phone market, currently dominated by iPhone, provided by Softbank Corp.

"We, of course, think (the Galaxy S) can compete with the iPhone," said DoCoMo President Ryuji Yamada.

The handset, which boasts a 4-inch multitouch screen, debuted in other countries several months ago, selling more than 5 million units worldwide so far.

Since the announcement of the Galaxy's debut earlier this month, "it has received really positive reactions, and we got more than 50,000 preorders from users," Yamada told reporters at Bic Camera in Tokyo's Yurakucho district.

While far fewer customers were on hand than for past iPhone debuts, Yamada added he hopes Galaxy sales match Xperia's, another smart phone introduced in April, which has sold about 500,000 units.

Galaxy S, known for its crisp display, called Super AMOLED, is 9.9 mm thick and 118 grams. It runs Google's Android OS 2.2 and is equipped with a 5-megapixel camera that can also shoot movies.

Customized for the Japanese market, the phone can receive mail from DoCoMo's i-mode service and is set up for a trial service of a planned DoCoMo e-book store.