General listening sites and apps
Presentations on all kinds of subjects that take between 4 and 25 minutes. App available.
BBC 6 minute learning
Every day a new video on a varied range of topics, 7 years of archives, so lots of choice.
Short videos for curious minds, videos on Youtube, so you can subscribe, between 3 - 8 minutes.
One of many apps with podcasts, radio and audiobooks. Also offline.
Others are Podcast Addict and Podcast App.