For the first time in her 20-year career cleaning houses in Philadelphia, Maria Del Carmen Diaz will soon be able to take a paid day off.

Diaz, a mother of three in her 50s who came to the United States in 1996, described it as a welcome benefit in a job that does not have many. No health care, no retirement fund, no contracts — which means that if a client pays her weeks late or cancels last-minute, which they do, she said, she has no recourse.

But paid time off is a step in the right direction, Diaz said in Spanish through an interpreter. And she's able to get it because of a new app from the National Domestic Workers Alliance (NDWA), called Alia.

Billed as the first "portable benefits" app of its kind — meaning benefits are tied to the worker, not the employer — Alia allows house cleaners to accrue paid sick days or other kinds of paid time off by collecting a small fee-per-job from clients. It was in beta testing for most of 2018 but launched to the public in December.

The app suggests a $5 contribution per cleaning, with a minimum of $5 a month. Cleaners have to accrue $120 in order to receive the benefit, which comes in the form of a prepaid Visa card.

The philosophy behind the app, she said, is that "domestic work should be protected and respected just like all work," said Palak Shah, who runs NDWA's innovation arm, Fair Care Labs.

But domestic work has long been left out of worker protection laws. A growing movement, led by NDWA, has fought to change this: New York state, California and Seattle have all passed a "Domestic Worker Bill of Rights," and a similar federal bill was introduced in November.

If Alia is successful, it could reverberate across many industries. NDWA and others who study domestic work like to say that domestic workers were the original "gig" workers.

Venture capitalists, co-founders and CEOs of on-demand companies like Lyft, Handy and Instacart have called for the development of portable benefits programs. In 2017, Google launched a $50 million fund to, among other things, improve the quality of low-wage work. One of its first grantees was NDWA.