NEW YORK — Samsung is expanding its lineup of tablet computers and making them look more like its Galaxy smartphones, as it hopes to translate its success in phones to the tablet market, where Apple is dominant.
Samsung Electronics Co., the second-largest maker of tablets after Apple, on Monday said it is putting three new tablets in the Galaxy Tab 3 series on sale in the United States on July 7. The cheapest, a $199 device, will have a screen that measures 7 inches diagonally. An 8-inch model will go for $299 and a 10-inch one for $399.
‘‘Our goal is to attract Galaxy smartphone users, and to make it the ultimate smartphone accessory,’’ said Shoneel Kolhatkar, director of product planning at Samsung Mobile.
The ‘‘Tab’’ line is Samsung’s value brand, undercutting the price of similar Apple models. Samsung’s premium tablets are in the ‘‘Note’’ line, and include styluses. The 7-inch and 10-inch tablets had ‘‘Tab 2’’ equivalents, but the 8-inch model is new, and coincides closely in size with Apple’s iPad Mini, which came out late last year.
The new tablets have the same three buttons on the front as the Galaxy smartphones. Last year’s Tab 2 had no physical buttons on the front, as encouraged by Google, which supplies the Android software.
The 7-inch Galaxy Tab 3 has 8 gigabytes of storage memory, while the larger models have 16 gigabytes. All of them have card slots for memory expansion.
Samsung had 18 percent of the global tablet market in the first quarter this year, according to research firm IDC. Apple had 40 percent.