Please note that once you move the app to SD card, the widget on the home screen will be unavailable. If you want to use widget, please move the app back to device memory.

To move Castbox app to SD card, please go to the phone Settings - Apps - Castbox - Storage - Change and set it to SD card. There may be a different path according to different phone models.

Eg: Samsung Galaxy S7 edge

For the previously downloaded episodes, we're afraid that you may not be able to move them directly. We suggest you finish listening to them first, then you could go to the app Settings, scroll down, tap "Change storage location" and set it to SD card as shown in pic.1&2. Thus, the newly downloaded episodes would be saved to your SD card.