Podcasts are typically audio broadcasts (like radio) available online. Depending on your needs and interests, you can subscribe to different channels. Once you have subscribed, updates in each of the channels will be automatically downloaded on your phone, and you can play them whilst travelling, cooking or just when you have the time to hear them.
To manage multiple podcasts, Podcast Addict is a wonderful app. You can download it on your phone once, and then search for various interesting channels. My favorites are TED Talks, Freakonomics, Harvard Busines Review(HBR) Ideacast and the $100 MBA Show. In the Indian context, I enjoy listening to NewsLaundry and CNN IBN. There is a whole load of interesting podcasts on cooking, music and regular radio, TV and news channels. Fish around and you will discover some real gems. Search by channel, interests and more, and Podcast Addict will come up with the goods.
Podcast Addict is free and it also allows you to stream live video now, along with your favorite YouTube channels. Try it out and share your own discoveries with me !