Six weeks after its debut inside yellow cabs roiled New York’s taxi industry, a cab-hailing app company said Tuesday that it would shut down the service, citing “obstacles and roadblocks” placed before it by the city.

The company, Uber, whose technology helps drivers and would-be passengers find one another, began operating the service last month in more than 100 taxis amid questions about whether the app violated the city’s guidelines, which prohibit prearranged rides in yellow taxis.

Travis Kalanick, the company’s chief executive, said that while passenger demand for the smartphone application was high, business faltered because drivers, fearing reprisal from the city’s Taxi and Limousine Commission, had not signed on in great enough numbers.