Perimeter

Perimeter, a small start-up in the Bay Area, makes collaborative mapping and data-sharing software for emergency workers. Its founder, Bailey Farren, is the 24-year-old daughter of a retired fire captain and a paramedic. After she and her family were forced to evacuate during the 2017 Tubbs fire, she saw the need for a better communication system than the two-way radios and paper maps that emergency workers often used. Perimeter's app, which allows fire departments to share real-time evacuation routes and safety updates, is being tested in California cities including Palo Alto and Petaluma, and the company plans to expand to other states soon.

– Kevin Roose