She checks the parking lots on her ParkMe smartphone app “so that I can see what I’m up against, or if I need to change my plans.” If a lot is below 90 percent full, the trip is on. Her favorite, not far from her workplace, is a garage at the Santa Monica Place mall, where sensors and lights guide her to a specific open space.

“It’s a daily battle,” said Ms. Scott, 29, the founder of Laudville, a social technology start-up. “Anything to make it easier makes a really big difference.”

The fight for a mall parking spot, long a necessary evil of Black Friday, is growing easier thanks to the proliferation of new technologies, from apps and sensors to color-coded lights and electronic boards.