MOUNTAIN VIEW, Calif. — Today’s demo day for 500 Startups’ newest class has taken a somber turn: It features not one, but two startups that are in the death business, and one uses the hot tech of the moment — drones.

PlotBox, hailing from Northern Ireland, has built cloud-based software that cemeteries and crematoria can use to better manage their operations. In particular, it uses drones to map the grounds and help cemeteries make sure they’re not burying anyone in the wrong plot – something that apparently happens and causes expensive lawsuits.

“We’re experts in cemetery mapping,” cofounder and chief executive Sean McAllister said during his presentation today at the Computer History Museum here in Mountain View.

McAllister is a licensed commercial drone pilot, which is how the company accurately maps out cemeteries for its software. Drones have been used for mapping in other industries, including agriculture, but clearly their scope is expanding.

The software provides tools for operations management, communicating with staff and other business partners, financial reporting, and making genealogy data searchable and available to the public.

There’s money to be made in the death biz. In the U.S. alone, it’s a $3 billion market, according to McAllister.

McAllister cofounder PlotBox with Leona McAllister, and they’re joined by chief technology officer Stephen Hardy.

The other startup in the category here today is Elwafeyat, “an online platform for obituary announcements and family tree mapping,” as the company describes itself.