Getting around without draining your phone battery

CONSERVING BATTERY LIFE: Instead of using satellites, Pathsense has written code that turns your phone into a navigation device similar to what's found on a submarine.

SAN FRANCISCO: For the most part, GPS works great. It gives people the ability to get from point A to point B with a simple press of a button on a smartphone. That's until you hit a big city. 

Tall buildings and satellite signals don't like each other and in an era where companies like Uber and Yelp depend on accurate navigation, Pete Tenereillo of California startup Pathsense has this to say.