For those needing long-term care, health managers initially visit a patient's home to evaluate the state of their health, and then formulate healthcare plans, Zhang says.

Even many nurses who have full-time jobs in hospitals take orders online to make extra money in their free time, Liu says.

"In a big city like Beijing there's huge demand for home nursing."

Pay for nurses working in hospitals is often very modest, especially compared with what doctors are paid, Liu says. She can now earn between 20,000 yuan and 30,000 yuan a month, more than double what nurses in hospitals are normally paid, she says.

"I used to work in an intensive care unit and had to work nonstop through the day, and often had to do overtime."

Her working hours are more flexible now, she says.

She also has a lot of job satisfaction now, she says, nursing elderly people confined to their beds and who need regular care for the replacement of gastric tubes or catheters.

She has developed close relationships with them, and many contact her for advice even after she has officially ceased nursing them.

"I've been with many elderly patients in the last stages of their lives. I like my current work because it gives me a sense of being needed and accepted. And I'm full of energy every day."

The internet-based nurse booking industry enjoyed a short boom in 2015, soon after it appeared, but most of the companies have failed to live up to their early promise, and the industry remains a fledgling.

In 2017 health authorities in Shanghai raised questions about how online nursing services were operating, with skeptical eyes being cast over the qualifications some of those working with them claimed to have.

In February the National Health Commission issued a guideline document on such services in cities and provinces including Beijing, Shanghai, Tianjin, Guangdong, Jiangsu and Zhejiang.