Radios may be a relic of the past, but audio technology is anything but outdated. In this week's Volvo Tech Drive, the Founder and CEO of Aaptiv, Ethan Agarwal, explains how his company is using audio to change the way the world works out.

Agarwal says that audio is making a resurgence thanks to voice assistants like Amazon Alexa. As the number of home assistants grow, investment in audio will grow as well.

Aaptiv is a subscription-based fitness app. Subscribers can get guided audio workouts for every type of exercise from cycling to weightlifting.