Practo Technologies, India's biggest doctor search provider, has acquired Qikwell Technologies, which offers a proprietary technology to manage patient transactions, to become the world's biggest doctor appointments booking company, the two Bangalore-based startups said Thursday.

Qikwell is the fourth acquisition in the last five months for Practo, which is backed by investors including Sequoia Capital and Tencent Holdings. It brings Practo, which already offers a mobile app through which people can look for doctors, further ability to help them plan their consultations and handle their payments via credit cards as well as mobile wallets.

With Qikwell onboard, Practo will handle nearly 40 million appointments a year, making it larger than companies such as ZocDoc Inc. in the U.S., Practo's co-founder and CEO Shashank ND said at a news conference in Bangalore, but declined to give financial details of the deal. Practo has so far raised about $125 million in three rounds of venture capital funding. The biggest of them was the latest, in which China's Tencent Holdings led a $90 million investment in the Bangalore startup, earlier this year.

Qikwell's two founders Krishna Prasad Chitrapura and Raghavendra Prasad TS, will, however, join the top management of Practo, Shashank said.

Four-year-old Qikwell, in which venture capital firm SAIF Partners invested $3 million about eight months ago in the startup's first round of venture funding, has a team of about 100 employees, which is expected to be fully absorbed into Practo, which has a current strength of about 2,000 employees.

Qikwell provides hospital appointment scheduling with presence across 250 hospitals in 19 cities, the companies said in a press release. Its customers include some of the country's biggest hospital chains, including Manipal Hospitals and Fortis Healthcare, with some 6,000 doctors and specialists on its network.

"The future is the transaction. Practo provides the doctor search, and Qikwell, the technology to know when exactly the doctor's available, when he's free and what time you can meet him on time," said Chitrapura, whose software resume starts with Novell Inc. He has a masters degree in computer science from the Indian Institute of Technology in Mumbai, and has previously worked with IBM Research and Yahoo Labs.

"Millions" of registered customers use Qikwell to pay for their doctors' consultations using stored credit cards or through two mobile wallets, currently, he said. The mobile wallet option was built into Qikwell about four months back. The two that can be used today are South Africa-based PayU and Paytm, from India's One97 Communications, in which China's e-commerce giant Alibaba Group Holding is one of the largest shareholders.