If you are not familiar with podcasts, they are an incredibly valuable way of keeping up with virtually any topic in a relatively passive manner. They are essentially on-demand radio shows that you can subscribe to. You can listen to them whenever you want like when driving, doing housework, or working out. That is why they are particularly valuable: they can turn relatively dull situations into fantastic learning opportunities.
Apple has a podcast app built right into iOS that you can use or there are also numerous other podcast apps on the app store that I recommend you check out. Most of these apps include discovery mechanisms that make it easier to find new podcasts and many podcasts will also talk about other podcasts they recommend.
It is hard to recommend specific podcasts because most development podcasts do not last particularly long. It takes a lot of time and energy to produce a podcast, so many people do it for a while and take long breaks or decide to stop after a while...